Lipid-based formulations for RNA delivery

Description

Technical Field

[0001] The present disclosure relates to compositions comprising RNA and a cationically ionizable lipid for delivering RNA to target tissues after administration, in particular after parenteral administration. The present disclosure also relates to methods for delivering RNA to cells of a subject or for treating or preventing a disease or disorder in a subject, wherein the methods comprise administering to a subject a composition of the present disclosure. The RNA compositions in some embodiments comprise single-stranded RNA such as mRNA which encodes a peptide or polypeptide of interest, such as a pharmaceutically active peptide or polypeptide. The RNA is taken up by cells of a target tissue and the RNA is translated into the encoded peptide or polypeptide, which may exhibit its physiological activity. Thus, the present disclosure also relates to methods for delivering a pharmaceutically active peptide or protein to a subject or for treating or preventing a disease or disorder in a subject, wherein the methods comprise administering to a subject an RNA composition of the present disclosure, wherein the RNA encodes the pharmaceutically active peptide or protein.Background

[0002] The use of RNA to deliver foreign genetic information into target cells offers an attractive alternative to DNA. The advantages of RNA include transient expression and non-transforming character. RNA does not require nucleus infiltration for expression and moreover cannot integrate into the host genome, thereby eliminating the risk of oncogenesis.

[0003] RNA can be delivered to a target through different vehicles, based mostly upon cationic polymers or lipids, which combine with the RNA to form nanoparticles. The nanoparticles are intended to protect the RNA from degradation, enable delivery of the RNA to the target site and facilitate cellular uptake and processing by the target cells. The efficiency of RNA delivery depends, in part, on the molecular composition of the nanoparticle and can be influenced by numerous parameters, including particle size, formulation, and charge or grafting with molecular moieties, such as polyethylene glycol (PEG) or other ligands. Nogueira et al. (ACS Appl. Nano Mater. 2020, 3, 10634-10645) discloses polysarcosine-functionalized lipid nanoparticles for therapeutic mRNA delivery.

[0004] There is a need of providing formulations for the delivery of pharmaceutically active RNA to a target tissue where the delivered RNA is efficiently translated into the peptide or polypeptide it codes for. The inventors surprisingly found that the RNA formulations described herein fulfill the above-mentioned requirements.Summary

[0005] The present invention generally provides a composition comprising RNA, a cationically ionizable lipid comprising the structure of formula (1) shown below, and at least one polysarcosine-conjugated lipid. The inventors found that RNA formulations containing this cationically ionizable lipid of formula (I) can be manufactured in a robust and reproducible manner. They are suitable as RNA delivery systems and display comparable characteristics with respect to known systems.

[0006] The RNA formulations described herein are useful as RNA delivery vehicles for in vivo application, such as for pharmaceutical application.

[0007] In a first aspect, the invention provides a composition comprising: (i) RNA; and (ii) a cationically ionizable lipid comprising the structure of the following formula (I): wherein each of R 1< and R 2< is independently R 5< or -G 1< -L 1< -R 6< , wherein at least one of R 1< and R 2< is -G 1< -L 1< -R 6< ; each of R 3< and R 4< is independently selected from the group consisting of C 1-6 alkyl, C 2-6 alkenyl, aryl, and C 3-10 cycloalkyl; each of R 5< and R 6< is independently a non-cyclic hydrocarbyl group having at least 10 carbon atoms; each of G 1< and G 2< is independently unsubstituted C 1-12 alkylene or C 2-12 alkenylene; each of L 1< and L 2< is independently selected from the group consisting of -O(C=O)-, -(C=O)O-, -C(=O)-, -O-, -S(O) x -, -S-S-, -C(=O)S-, -SC(=O)-, -NR a< C(=O)-, -C(=O)NR a< -, -NR a< C(=O)NR a< -, -OC(=O)NR a< - and -NR a< C(=O)O-; R a< is H or C 1-12 alkyl; m is 0, 1, 2, 3, or 4; and x is 0, 1 or 2.

[0008] In some embodiments, each L 1< is independently selected from the group consisting of -O(C=O)-, -(C=O)O-, -C(=O)S-, -SC(=O)-, -NR a< C(=O)-, and -C(=O)NR a< -. In some embodiments, each L 1< is independently -O(C=O)- or -(C=O)O-.

[0009] In some embodiments, L 2< is selected from the group consisting of -O(C=O)-, -(C=O)O-, -C(=O)-, -C(=O)S-, -SC(=O)-, -NR a< C(=O)-, and -C(=O)NR a< -. In some embodiments, L 2< is -O(C=O)- or -(C=O)O-.

[0010] In some embodiments, R 5< is a straight alkyl or alkenyl group having at least 10 carbon atoms, preferably at least 14 carbon atoms, more preferably at least 16 carbon atoms. In some embodiments, R 5< is a straight alkyl group or a straight alkenyl group having at least 2 carbon-carbon double bonds. In some embodiments, R 5< has the following structure: wherein represents the bond by which R 5< is bound to the remainder of the compound. In some embodiments, each G 1< is independently unsubstituted straight C 1-12 alkylene or C 2-12 alkenylene, preferably unsubstituted, straight C 6-12 alkylene or C 6-12 alkenylene. In some embodiments, each G 1< is independently unsubstituted, straight C 8-12 alkylene or C 8-12 alkenylene, such as unsubstituted straight C 6-10 alkylene or C 6-10 alkenylene. In some embodiments, each G 1< is unsubstituted straight C 8 alkylene.

[0011] In some embodiments, each R 6< is independently a straight hydrocarbyl group having at least 10 carbon atoms. In some embodiments, each R 6< is attached to L 1< via an internal carbon atom of R 6< . In some embodiments, each R 6< is independently selected from the group consisting of: and wherein represents the bond by which R 6< is bound to L 1< .

[0012] In some embodiments, one of R 1< and R 2< is R 5< and the other is -G 1< -L 1< -R 6< .

[0013] In some embodiments, each of R 1< and R 2< is independently -G 1< -L 1< -R 6< .

[0014] In some embodiments, each of R 3< and R 4< is independently C 1-6 alkyl or C 2-6 alkenyl, preferably C 1-4 alkyl or C 2-4 alkenyl. In some embodiments, each of R 3< and R 4< is C 1-3 alkyl, such as methyl or ethyl. In some embodiments, each of R 3< and R 4< is methyl.

[0015] In some embodiments, G 2< is unsubstituted C 2-10 alkylene or C 2-10 alkenylene, preferably unsubstituted C 2-6 alkylene or C 2-6 alkenylene. In some embodiments, G 2< is unsubstituted C 2-4 alkylene or C 2-4 alkenylene, such as ethylene or trimethylene.

[0016] In some embodiments, m is 0, 1, 2 or 3. In some embodiments m is 0. In some embodiments, m is 2.

[0017] In some embodiments, the cationically ionizable lipid comprises the structure of one of the following formulas (IIIa) or (IIIb): wherein each of R 3< and R 4< is independently C 1-4 alkyl or C 2-4 alkenyl; R 5< is a straight alkyl or alkenyl group having at least 16 carbon atoms; each R 6< is independently a straight hydrocarbyl group having at least 10 carbon atoms, wherein R 6< is attached to L 1< via an internal carbon atom of R 6< ; each G 1< is independently unsubstituted, straight C 6-12 alkylene or C 6-12 alkenylene; G 2< is unsubstituted C 2-6 alkylene or C 2-6 alkenylene; each of L 1< and L 2< is independently -O(C=O)- or -(C=O)O-; and m is 0, 1, 2 or 3.

[0018] In some embodiments, each of R 3< and R 4< is C 1-3 alkyl, such as methyl or ethyl.

[0019] In some embodiments, R 5< is a straight alkyl or alkenyl group having at least 16 carbon atoms, wherein the alkenyl group has at least 2 carbon-carbon double bonds.

[0020] In some embodiments, each G 1< is independently unsubstituted, straight C 8-10 alkylene or unsubstituted, straight C 8-10 alkenylene, such as unsubstituted, straight C 8 alkylene.

[0021] In some embodiments, G 2< is unsubstituted C 2-4 alkylene or C 2-4 alkenylene, such as ethylene or trimethylene.

[0022] In some embodiments, m is 0. In some embodiments, m is 2.

[0023] In some embodiments, the cationically ionizable lipid comprises one of the following structures (IV-1), (IV-2), and (IV-3):

[0024] In some embodiments, the cationically ionizable lipid comprises from about 20 mol % to about 80 mol %, preferably from about 25 mol % to about 65 mol %, more preferably from about 30 mol % to about 50 mol % of the total lipid present in the composition. In some embodiments, the cationically ionizable lipid comprises from about 40 mol % to about 50 mol % of the total lipid present in the composition. In some embodiments, the cationically ionizable lipid comprises from about 55 mol % to about 65 mol % of the total lipid present in the composition.

[0025] The composition further comprises a polymer-conjugated lipid.

[0026] The polymer-conjugated lipid is a polysarcosine-conjugated lipid. Thus, the composition further comprises at least one polysarcosine-conjugated lipid (such as two or more polysarcosine-conjugated lipids).

[0027] In some embodiments, the polysarcosine comprises between 2 and 200 sarcosine units, preferably between 5 and 100 sarcosine units, more preferably between 10 and 50 sarcosine units, more preferably between 15 and 40 sarcosine units, more preferably about 23 sarcosine units.

[0028] In some embodiments, the polysarcosine-conjugated lipid comprises the structure of the following general formula (V): wherein x is the number of sarcosine units.

[0029] In some embodiments, the polysarcosine-conjugated lipid has the structure of the following general formula (VI): wherein one of R 1< and R 2< comprises a hydrophobic group and the other is H, a hydrophilic group or a functional group optionally comprising a targeting moiety; and x is the number of sarcosine units. In some embodiments, R 1< is H, a hydrophilic group or a functional group optionally comprising a targeting moiety; and R 2< comprises one or two straight alkyl or alkenyl groups each having at least 12 carbon atoms, preferably at least 14 carbon atoms.

[0030] In some embodiments, the polysarcosine-conjugated lipid has the structure of the following general formula (VII): wherein R is H, a hydrophilic group or a functional group optionally comprising a targeting moiety; and x is the number of sarcosine units.

[0031] In some embodiments, the polysarcosine-conjugated lipid has the structure of the following formula (VII-1): wherein n is 23.

[0032] In some embodiments, the polysarcosine-conjugated lipid comprises from about 0.1 mol % to about 5 mol % of the total lipid present in the composition. In some embodiments, the polysarcosine-conjugated lipid comprises from about 0.5 mol % to about 4.5 mol % of the total lipid present in the composition. In some embodiments, the polysarcosine-conjugated lipid comprises from about 1 mol % to about 4 mol % of the total lipid present in the composition. In some embodiments, the polysarcosine-conjugated lipid comprises from about 3 mol % to about 4 mol % of the total lipid present in the composition.

[0033] In some embodiments, the polymer-conjugated lipid is a pegylated lipid.

[0034] In some embodiments, the pegylated lipid has the structure of the following general formula (VIII): or a pharmaceutically acceptable salt, tautomer or stereoisomer thereof, wherein: each of R 12< and R 13< is each independently a straight or branched alkyl, alkenyl, or alkynyl chain, wherein each of the alkyl, alkenyl, and alkynyl chains independently contains from 10 to 30 carbon atoms and is optionally interrupted by one or more ester bonds; and w has a mean value ranging from 30 to 60. In some embodiments, each of R 12< and R 13< is independently a straight alkyl chain containing from 10 to 18 carbon atoms, preferably from 12 to 16 carbon atoms. In some embodiments, R 12< and R 13< are identical. In some embodiments, each of R 12< and R 13< is a straight alkyl chain containing 12 carbon atoms. In some embodiments, each of R 12< and R 13< is a straight alkyl chain containing 14 carbon atoms. In some embodiments, each of R 12< and R 13< is a straight alkyl chain containing 16 carbon atoms. In some embodiments, R 12< and R 13< are different. In some embodiments, one of R 12< and R 13< is a straight alkyl chain containing 12 carbon atoms and the other of R 12< and R 13< is a straight alkyl chain containing 14 carbon atoms. In some embodiments, z has a mean value ranging from 40 to 50, such as a mean value of 45.

[0035] In some embodiments, the pegylated lipid comprises from about 1 mol % to about 10 mol % of the total lipid present in the composition. In some embodiments, the pegylated lipid comprises from about 1 mol % to about 5 mol % of the total lipid present in the composition. In some embodiments, the pegylated lipid comprises from about 1 mol % to about 2.5 mol % of the total lipid present in the composition.

[0036] In some embodiments, the composition further comprises one or more additional lipids. In some embodiments, the one or more additional lipids are selected from the group consisting of phospholipids, steroids, and combinations thereof.

[0037] In some embodiments, the composition comprises the cationically ionizable lipid; a polymer-conjugated lipid; a phospholipid; and a steroid.

[0038] According to the invention, the composition comprises at least one polysarcosine-conjugated lipid.

[0039] In some embodiments, the phospholipid is selected from the group consisting of phosphatidylcholines, phosphatidylethanolamines, phosphatidylglycerols, phosphatidic acids, phosphatidylserines and sphingomyelins, more preferably selected from the group consisting of distearoylphosphatidylcholine (DSPC), dioleoylphosphatidylcholine (DOPC), dimyristoylphosphatidylcholine (DMPC), dipentadecanoylphosphatidylcholine, dilauroylphosphatidylcholine, dipalmitoylphosphatidylcholine (DPPC), diarachidoylphosphatidylcholine (DAPC), dibehenoylphosphatidylcholine (DBPC), ditricosanoylphosphatidylcholine (DTPC), dilignoceroylphatidylcholine (DLPC), palmitoyloleoyl-phosphatidylcholine (POPC), 1,2-di-O-octadecenyl-sn-glycero-3-phosphocholine (18:0 Diether PC), 1-oleoyl-2-cholesterylhemisuccinoyl-sn-glycero-3-phosphocholine (OChemsPC), 1-hexadecyl-sn-glycero-3-phosphocholine (C16 Lyso PC), dioleoylphosphatidylethanolamine (DOPE), distearoyl-phosphatidylethanolamine (DSPE), dipalmitoyl-phosphatidylethanolamine (DPPE), dimyristoyl-phosphatidylethanolamine (DMPE), dilauroyl-phosphatidylethanolamine (DLPE), and diphytanoyl-phosphatidylethanolamine (DPyPE). In some embodiments, the phospholipid is DSPC. In some embodiments, the phospholipid is DOPE.

[0040] In some embodiments, the phospholipid comprises from about 5 mol % to about 40 mol % of the total lipid present in the composition. In some embodiments, the phospholipid comprises from about 5 mol % to about 20 mol % of the total lipid present in the composition. In some embodiments, the phospholipid comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition.

[0041] In some embodiments, the steroid comprises a sterol such as cholesterol.

[0042] In some embodiments, the steroid comprises from about 10 mol % to about 65 mol % of the total lipid present in the composition. In some embodiments, the steroid comprises from about 20 mol % to about 60 mol % of the total lipid present in the composition. In some embodiments, the steroid comprises from about 30 mol % to about 50 mol % of the total lipid present in the composition. In some embodiments, the steroid comprises from about 25 mol % to about 35 mol % of the total lipid present in the composition.

[0043] In some embodiments, the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-1) or (IV-3), more preferably (IV-3); the polysarcosine-conjugated lipid has formula (VII-1); the phospholipid is DSPC; and the steroid is cholesterol.

[0044] In some embodiments, the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-2); the polysarcosine-conjugated lipid has formula (VII-1); the phospholipid is DOPE; and the steroid is cholesterol.

[0045] In some embodiments, the composition comprises the cationically ionizable lipid, a pegylated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-1) or (IV-3), more preferably (IV-3); the pegylated lipid is DMG-PEG 2000; the phospholipid is DSPC; and the steroid is cholesterol.

[0046] In some embodiments, the composition comprises the cationically ionizable lipid, a pegylated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-2); the pegylated lipid is DMG-PEG 2000; the phospholipid is DOPE; and the steroid is cholesterol.

[0047] In some embodiments, the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from about 30 mol % to about 50 mol of the total lipid present in the composition; the polysarcosine-conjugated lipid comprises from about 1 mol % to about 4.5 mol %, such as from about 3 mol % to about 4 mol %, of the total lipid present in the composition; the phospholipid comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid comprises from about 30 mol % to about 50 mol % of the total lipid present in the composition. In some embodiments, the cationically ionizable lipid comprises from about 40 mol % to about 50 mol % of the total lipid present in the composition.

[0048] In some embodiments, the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from about 40 mol % to about 50 mol of the total lipid present in the composition; the polysarcosine-conjugated lipid comprises from about 3 mol % to about 4 mol % of the total lipid present in the composition; the phospholipid comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid comprises from about 35 mol % to about 45 mol % of the total lipid present in the composition. In some of these embodiments, the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-3); the polysarcosine-conjugated lipid has formula (VII-1); the phospholipid is DSPC; and the steroid is cholesterol. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0049] In some embodiments, the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-3), and comprises from about 40 mol % to about 50 mol of the total lipid present in the composition; the polysarcosine-conjugated lipid has formula (VII-1) and comprises from about 3 mol % to about 4 mol % of the total lipid present in the composition; the phospholipid is DSPC and comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid is is cholesterol and comprises from about 35 mol % to about 45 mol % of the total lipid present in the composition. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0050] In some embodiments, the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from about 55 mol % to about 65 mol % of the total lipid present in the composition; the polysarcosine-conjugated lipid comprises from about 1 mol % to about 4.5 mol %, such as from about 3 mol % to about 4 mol %, of the total lipid present in the composition; the phospholipid comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid comprises from about 25 mol % to about 35 mol % of the total lipid present in the composition. In some of these embodiments, the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-2); the polysarcosine-conjugated lipid has formula (VII-1); the phospholipid is DOPE; and the steroid is cholesterol. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0051] In some embodiments, the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-2) and comprises from about 55 mol % to about 65 mol % of the total lipid present in the composition; the polysarcosine-conjugated lipid has formula (VII-1) and comprises from about 1 mol % to about 4.5 mol %, such as from about 3 mol % to about 4 mol %, of the total lipid present in the composition; the phospholipid is DOPE and comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid is cholesterol and comprises from about 25 mol % to about 35 mol % of the total lipid present in the composition. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0052] In some embodiments, the composition comprises the cationically ionizable lipid, a pegylated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from about 30 mol % to about 50 mol % of the total lipid present in the composition; the pegylated lipid comprises from about 1 mol % to about 2.5 mol % of the total lipid present in the composition; the phospholipid comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid comprises from about 30 mol % to about 50 mol % of the total lipid present in the composition. In some embodiments, the cationically ionizable lipid comprises from about 40 mol % to about 50 mol % of the total lipid present in the composition.

[0053] In some embodiments, the composition comprises the cationically ionizable lipid, a pegylated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from about 40 mol % to about 50 mol of the total lipid present in the composition; the pegylated lipid comprises from about 1 mol % to about 2.5 mol % of the total lipid present in the composition; the phospholipid comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid comprises from about 35 mol % to about 45 mol % of the total lipid present in the composition. In some of these embodiments, the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-3); the pegylated lipid is DMG-PEG 2000; the phospholipid is DSPC; and the steroid is cholesterol. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0054] In some embodiments, the composition comprises the cationically ionizable lipid, a pegylated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-3) and comprises from about 40 mol % to about 50 mol of the total lipid present in the composition; the pegylated lipid is DMG-PEG 2000 and comprises from about 1 mol % to about 2.5 mol % of the total lipid present in the composition; the phospholipid is DSPC and comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid is cholesterol and comprises from about 35 mol % to about 45 mol % of the total lipid present in the composition. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0055] In some embodiments, the composition comprises the cationically ionizable lipid, a pegylated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from about 55 mol % to about 65 mol % of the total lipid present in the composition; the pegylated lipid comprises from about 1 mol % to about 2.5 mol % of the total lipid present in the composition; the phospholipid comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid comprises from about 25 mol % to about 35 mol % of the total lipid present in the composition. In some of these embodiments, the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-2); the pegylated lipid is DMG-PEG 2000; the phospholipid is DOPE; and the steroid is cholesterol. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0056] In some embodiments, the composition comprises the cationically ionizable lipid, a pegylated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid is one of the structures (IV-1), (IV-2), and (IV-3), preferably (IV-2) and comprises from about 55 mol % to about 65 mol of the total lipid present in the composition; the pegylated lipid is DMG-PEG 2000 and comprises from about 1 mol % to about 2.5 mol % of the total lipid present in the composition; the phospholipid is DOPE and comprises from about 5 mol % to about 15 mol % of the total lipid present in the composition; and the steroid is cholesterol and comprises from about 25 mol % to about 35 mol % of the total lipid present in the composition. In some of these embodiments, the N / P value in the composition is at least about 4. In some embodiments, the N / P value ranges from 4 to 20, 4 to 12, 4 to 10, 4 to 8, or 5 to 7. In some embodiments, the N / P value is about 6. In some embodiments, the N / P value is about 8. In some embodiments, the N / P value is about 12.

[0057] In some embodiments, at least a portion of (i) the RNA, (ii) the cationically ionizable lipid, and, if present, (iii) the one or more additional lipids is present in nanoparticles, such as lipid nanoparticles (LNPs).

[0058] In some embodiments, the nanoparticles (such as LNPs) have a size of from about 30 nm to about 500 nm. In some embodiments, the nanoparticles have a size of from about 40 nm to about 200 nm, such as from about 50 nm to about 180 nm, from about 60 nm to about 160 nm, from about 80 nm to about 150 nm or from about 80 nm to about 120 nm.

[0059] In some embodiments, the RNA is mRNA.

[0060] In some embodiments, the RNA comprises a modified nucleoside in place of uridine. In some embodiments, the modified nucleoside is selected from pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine (m5U).

[0061] In some embodiments, the RNA has a coding sequence which is codon-optimized.

[0062] In some embodiments, has a coding sequence whose G / C content is increased compared to the wild-type coding sequence.

[0063] In some embodiments, the RNA (i) comprises a modified nucleoside in place of uridine; (ii) has a coding sequence which is codon-optimized; and (iii) has a coding sequence whose G / C content is increased compared to the wild-type coding sequence. In some embodiments, the modified nucleoside is selected from pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine (m5U).

[0064] In some embodiments, the RNA comprises at least one of the following: a 5' cap; a 5' UTR; a 3' UTR; and a poly-A sequence.

[0065] In some embodiments, the RNA comprises all of the following: a 5' cap; a 5' UTR; a 3' UTR; and a poly-A sequence.

[0066] In some embodiments, the poly-A sequence comprises at least 100 A nucleotides. In some embodiments, the poly-A sequence is an interrupted sequence of A nucleotides.

[0067] In some embodiments, the 5' cap is a cap1 structure. In some embodiments, the 5' cap is cap2 structure.

[0068] In some embodiments, the RNA encodes one or more peptides or proteins. In some embodiments, the one or more peptides or proteins are pharmaceutically active peptides or proteins. In some embodiments, the one or more peptides or proteins comprise an epitope for inducing an immune response against an antigen in a subject. In some embodiments, the one or more peptides or proteins are pharmaceutically active peptides or proteins and comprise an epitope for inducing an immune response against an antigen in a subject.

[0069] In some embodiments, the pharmaceutically active peptide or protein and / or the antigen or epitope is derived from or is a SARS-CoV-2 spike (S) protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof. In some embodiments, the RNA comprises an open reading frame (ORF) encoding an amino acid sequence comprising a SARS-CoV-2 S protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof.

[0070] In some embodiments, the SARS-CoV-2 S protein variant has proline residue substitutions at positions 986 and 987 of SEQ ID NO: 11.

[0071] In some embodiments, the SARS-CoV-2 S protein variant has at least 80% identity to the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 11 or the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 12.

[0072] In some embodiments, the fragment comprises the receptor binding domain (RBD) of the SARS-CoV-2 S protein.

[0073] In some embodiments, the fragment of (i) the SARS-CoV-2 S protein or (ii) the immunogenic variant of the SARS-CoV-2 S protein has at least 80% identity to the amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11.

[0074] In a second aspect, the invention provides a method for delivering RNA to cells of a subject, the method comprising administering to a subject a composition of the first aspect. In some embodiments of the second aspect, the composition is administered parenterally, such as intramuscularly.

[0075] In a third aspect, the invention provides a method for delivering a pharmaceutically active peptide or protein to a subject, the method comprising administering to a subject a composition of the first aspect, wherein the RNA encodes the pharmaceutically active peptide or protein. In some embodiments of the third aspect, the composition is administered parenterally, such as intramuscularly.

[0076] In a fourth aspect, the invention provides a method for treating or preventing a disease or disorder in a subject, the method comprising administering to a subject a composition of the first aspect, wherein delivering the RNA to cells of the subject is beneficial in treating or preventing the disease or disorder. In some embodiments of the fourth aspect, the composition is administered parenterally, such as intramuscularly.

[0077] In a fifth aspect, the invention provides a method for treating or preventing a disease or disorder in a subject, the method comprising administering to a subject a composition of the first aspect, wherein the RNA encodes a pharmaceutically active peptide or protein and wherein delivering the pharmaceutically active peptide or protein to the subject is beneficial in treating or preventing the disease or disorder. In some embodiments of the fifth aspect, the composition is administered parenterally, such as intramuscularly.

[0078] Further embodiments of the above aspects are described herein.

[0079] In some embodiments, the RNA described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is single-stranded RNA (in particular, mRNA) that may be translated into the respective protein upon entering cells, e.g., cells of a recipient. In addition to wild-type or codon-optimized sequences encoding an amino acid sequence comprising the amino acid sequence of a peptide or polypeptide having biological activity, e.g., a pharmaceutically active peptide or polypeptide such as antigen sequence (peptide or polypeptide comprising an epitope), the RNA may contain one or more structural elements optimized for maximal efficacy of the RNA with respect to stability and translational efficiency (5' cap, 5' UTR, 3' UTR, poly(A)-tail). In some embodiments, the RNA contains all of these elements. In some embodiments, beta-S-ARCA(D1) (m 2 7,2'-O< GppSpG) or m 2 7,3'-O< Gppp(m 1 2'O< )ApG may be utilized as specific capping structure at the 5'-end of the RNA drug substances. As 5'-UTR sequence, the 5'-UTR sequence of the human alpha-globin mRNA, optionally with an optimized 'Kozak sequence' to increase translational efficiency may be used. As 3'-UTR sequence, a combination of two sequence elements (FI element) derived from the "amino terminal enhancer of split" (AES) mRNA (called F) and the mitochondrial encoded 12S ribosomal RNA (called I) placed between the coding sequence and the poly(A)-tail to assure higher maximum protein levels and prolonged persistence of the mRNA may be used. These were identified by an ex vivo selection process for sequences that confer RNA stability and augment total protein expression (see WO 2017 / 060314).

[0080] Alternatively, the 3'-UTR may be two re-iterated 3'-UTRs of the human beta-globin mRNA. Furthermore, a poly(A)-tail measuring 110 nucleotides in length, consisting of a stretch of 30 adenosine residues, followed by a 10 nucleotide linker sequence (of random nucleotides) and another 70 adenosine residues may be used. This poly(A)-tail sequence was designed to enhance RNA stability and translational efficiency.

[0081] The amino acid sequence comprising the amino acid sequence of a peptide or polypeptide having biological activity, e.g., a pharmaceutically active peptide or polypeptide such as antigen sequence, may comprise amino acid sequences other than the amino acid sequence of a peptide or polypeptide having biological activity. Such other amino acid sequences may support the function or activity of the peptide or polypeptide having biological activity. In some embodiments, such other amino acid sequences comprise an amino acid sequence enhancing antigen processing and / or presentation. Alternatively, or additionally, such other amino acid sequences comprise an amino acid sequence which breaks immunological tolerance.Brief description of the Figures

[0082] Figure 1. Characteristics of RNA LNP formulations containing different cationically ionizable lipids of formula (I) disclosed herein (i.e., lipid EA-405, HY-405, or HY-501) and the polysarcosine-conjugated lipid C14pSar23 (abbreviated as "pSar" in the figure): (A) particle size and PDI; (B) zeta-potential; (C) accessible RNA; and (D) free RNA (lane 1: EA-405_pSar, lane 2: HY-405_pSar, lane 3: HY-501_pSar, lane 4: EA-405-NP6_47.5%, lane 5: HY-405-NP6_47.5%, lane 6: HY-501-NP6_47.5%). Figure 2. (A) In vitro expression and (B) viability of RNA LNP formulations containing different cationically ionizable lipids (EA-405, HY-405, and HY-501) in skeletal muscle cell line (C2C12), a hepatocarcinoma cell line (HepG2) and a murine macrophage cell line (Raw cell). Firefly luciferase expression 24h post-incubation with 12.5, 25 and 50 ng per well of mRNA-loaded LNPs. Figure 3. (A) In vivo whole body bioluminescence imaging (BLI) of animals (n=3) at 6h (upper row), 24h (middle row) and ex-vivo BLI (bottom row). (B) In vivo luciferase expression in muscle region 6 and 24 h post-transfection for the LNP formulations containing different cationically ionizable lipids and C14pSar23. Figure 4. (A) Terminal complement complex (SC5b-9) formation after incubation of human serum with LNPs containing different cationically ionizable lipids and control items. The horizontal dashed line shows the level of SC5b-9 formation for PBS. (B) Hemolysis analysis after incubation (in neutral pH condition) of human red blood cells with LNP formulations containing different cationically ionizable lipids and controls. Figure 5. Characteristics of RNA LNP formulations containing HY-501 and C14pSar23: (A) particle size and PDI; (B) zeta-potential; (C) accessible RNA; and (D) free RNA. Figure 6. (A) Terminal complement complex (SC5b-9) formation after incubation of human serum with HY-501 containing LNP formulations and control items. The horizontal dashed line shows the level of SC5b-9 formation for PBS. (B) Hemolysis analysis after incubation (in neutral pH condition) of whole human blood with HY-501 containing LNP formulations. Figure 7. Quantification of S1 protein expression after transfection with C14pSar23 containing LNPs using HY-501 as cationic lipid. (A) Variation in pSar mol% vs. MFI (Mean Fluorescence Intensity) of the overall cell population. Data was fitted using a quadratic polynomial function. (B) Viability of all tested formulations. Plotted are mean values (n=3) ± StDev. Figure 8. Characteristics of RNA LNP formulations containing HY-405 and C14pSar23: (A) particle size and PDI; (B) zeta-potential; (C) accessible RNA; and (D) free RNA. Figure 9. (A) Terminal complement complex (SCSb-9) formation after incubation of human serum with LNP formulations and control items. The horizontal dashed line shows the level of SCSb-9 formation for PBS. The horizontal dashed line shows the level of SC5b-9 formation for PBS. (B) Hemolysis analysis after incubation (in neutral pH condition) of whole human blood with HY405 containing LNP formulations. Figure 10. (A) Accessible RNA measured via Ribogreen Assay. (B) Agarose gel electrophoresis image of LNP formulations containing HY501 or HY405 (first injection). Figure 11. (A) Accessible RNA measured via Ribogreen Assay. (B) Agarose gel electrophoresis image of LNP formulations containing HY501 or HY405 (second injection). Figure 12. Quantification of S1 protein expression after transfection with LNP formulations containing HY405 or HY501. (A) MFI (Mean Fluorescence Intensity) of the overall cell population. (B) Viability of all tested formulations. Plotted are mean values (n=3) + / - standard deviation (SD). Figure 13. Quantification of S1 protein expression after transfection with LNP formulations containing BM, HY405 or HY501. MFl: Mean Fluorescence Intensity of the overall cell population. Viability is viability of all tested formulations. Plotted are mean values (n=3) + / -SD. Figure 14. Serological analysis using anti-S1-ELISA to detect SARS-CoV-2 S protein specific antibodies; after first immunization, animals were bled weekly and serological analysis was performed. Figure 15. Graphs showing the pVNT 50 values for group 2 (HY-501), group 3 (HY-405) and control (PBS) at different time points (D29, D28, D35, D42, D49, D56). Figure 16. Graphs showing IFNy-secretion from splenocytes after restimulation with (A) an overlapping peptide mix specific for the SARS-CoV-2 S protein, (B) SARS-CoV-2 RBD peptide pool, or (C) unrelated peptide. Figure 17. Physicochemical characteristics of EA-405, HY-501, HY-405 LNP formulations including (A) size and polydispersity index (PDI), (B) zeta potential and (C) encapsulation efficiency, RNA accessibility and free RNA. Figure 18. Representative (A) in vivo dorsal, (B) in vivo ventral, and (C) ex vivo bioluminescence images (BLI) of BALB / c mice injected with 1 µg / leg modified mRNA coding for luciferase via intramuscular route over time. Relative luminescence scale is indicated. For (C), organs are set from top to bottom as following: heart, lung, liver, spleen, kidneys. Figure 19. Quantification of the bioluminescent signal measured in BALB / c mice injected with 1 µg / leg LNPs containing modified mRNA coding for luciferase 6 h post-injection in (A) muscle, (B) liver regions in vivo, (C) spleen and (D) organs ex vivo. Data represent the mean of 3 mice / group (n=3) ± SD for in vivo BLI and 1 mouse / group (n=1) for ex vivo BLI, expressed as total flux (photons / sec). Figure 20. Physicochemical characteristics of LNP optimization in terms of N / P ratio (3-12). Bar graphs include size and charge (a, b, and c), encapsulation efficiency and RNA accessibility (d, e, and f) and free RNA (g, h, and i) of formulations containing EA-405, HY-501 and HY-405, respectively. Figure 21. In vitro luciferase expression of EA-405 (a, b, and c), HY-501 (d, e, and f) and HY-405 (g, h, and i) in C2C12, HepG2 and RAW cell lines using 12.5 ng, 25 ng and 50 ng mRNA dose. Figure 22. Representative (A) in vivo dorsal, (B) in vivo ventral, and (C) ex vivo bioluminescence images (BLI) of BALB / c mice injected with 1 µg / leg mod. mRNA-luciferase containing LNPs with different N / P ratios, via intramuscular route over 48 h. Relative luminescence scale is indicated accordingly. For (C), organs are set from top to bottom as following: heart, lung, liver, spleen, kidneys. Figure 23. Quantification of the bioluminescent signal measured in BALB / c mice injected with 1 µg / leg LNPs containing mod. mRNA coding for luciferase (with different N / P ratios; 4, 6 and 12) 6 h post-injection in (a) muscle, (b) liver regions in vivo, (c) spleen and (d) organs ex vivo. Data represent the mean of 3 mice / group (n=3) ± SD for in vivo BLI and 1 mouse / group (n=1) for ex vivo BLI, expressed as total flux (photons / sec). Figure 24. Antibody titers (measured by ELISA) of EA-405, HY-501 and HY-405 formulations vs. BM and buffer control (PBS) at (a) day 14 after prime, (b) day 28 after boost and (c) day 42 as endpoint. IFN-y ELISpot analysis (d) performed with total splenocytes collected at day 42. Figure 25. Physicochemical characteristics of EA-405 LNPs in terms of (a) size and polydispersity index (PDI), (b) zeta potential, (c) encapsulated RNA / accessible RNA and (d) free RNA. Figure 26. Representative (A) in vivo dorsal and (B) in vivo ventral bioluminescence images (BLI) of BALB / c mice injected with 1 µg / leg mod. mRNA coding for luciferase via intramuscular route at 6 h (A and B) and 24 h (only A). Relative luminescence scale is indicated. Figure 27. Quantification of bioluminescent signal measured in BALB / c mice injected with 1 µg / leg LNPs containing luciferase encoding mod. mRNA in (a) muscle (6 h and 24 h post-injection); (b) muscle (over 9 days "kinetics"); (c) liver (in vivo expressed as total flux (photons / sec)); (d) IFN-y ELISpot analysis. Data represent the mean of 3 mice / group and 2 sites (n=6) ± SD for in vivo BLI and 3 mouse / group (n=3) for liver and ELISpot. Description of the Sequences

[0083] The following table provides a listing of certain sequences referenced herein. Detailed Description of the Invention

[0084] Although the present disclosure is further described in more detail below, it is to be understood that this disclosure is not limited to the particular methodologies, protocols and reagents described herein as these may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present disclosure which will be limited only by the appended claims. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art.

[0085] In the following, the elements of the present disclosure will be described in more detail. These elements are listed with specific embodiments, however, it should be understood that they may be combined in any manner and in any number to create additional embodiments. The variously described examples and preferred embodiments should not be construed to limit the present disclosure to only the explicitly described embodiments. This description should be understood to support and encompass embodiments which combine the explicitly described embodiments with any number of the disclosed and / or preferred elements. Furthermore, any permutations and combinations of all described elements in this application should be considered disclosed by the description of the present application unless the context indicates otherwise.

[0086] The practice of the present disclosure will employ, unless otherwise indicated, conventional chemistry, biochemistry, cell biology, immunology, and recombinant DNA techniques which are explained in the literature in the field.

[0087] Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated feature, element, member, integer or step or group of features, elements, members, integers or steps but not the exclusion of any other feature, element, member, integer or step or group of features, elements, members, integers or steps. The term "consisting essentially of" limits the scope of a claim or disclosure to the specified features, elements, members, integers, or steps and those that do not materially affect the basic and novel characteristic(s) of the claim or disclosure. The term "consisting of" limits the scope of a claim or disclosure to the specified features, elements, members, integers, or steps. The term "comprising" encompasses the term "consisting essentially of" which, in turn, encompasses the term "consisting of". Thus, at each occurrence in the present application, the term "comprising" may be replaced with the term "consisting essentially of" or "consisting of". Likewise, at each occurrence in the present application, the term "consisting essentially of" may be replaced with the term "consisting of".

[0088] The terms "a", "an" and "the" and similar references used in the context of describing the present disclosure (especially in the context of the claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by the context.

[0089] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by the context.

[0090] The use of any and all examples, or exemplary language (e.g., "such as"), provided herein is intended merely to better illustrate the present disclosure and does not pose a limitation on the scope of the present disclosure otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the present disclosure.

[0091] The term "optional" or "optionally" as used herein means that the subsequently described event, circumstance or condition may or may not occur, and that the description includes instances where said event, circumstance, or condition occurs and instances in which it does not occur.

[0092] Where used herein, "and / or" is to be taken as specific disclosure of each of the two specified features or components with or without the other. For example, "X and / or Y" is to be taken as specific disclosure of each of (i) X, (ii) Y, and (iii) X and Y, just as if each is set out individually herein.

[0093] In the context of the present disclosure, the term "about" denotes an interval of accuracy that the person of ordinary skill will understand to still ensure the technical effect of the feature in question. The term typically indicates deviation from the indicated numerical value by ±10%, ±5%, ±4%, ±3%, ±2%, ±1%, ±0.9%, ±0.8%, ±0.7%, ±0.6%, ±0.5%, ±0.4%, ±0.3%, ±0.2%, ±0.1%, ±0.05%, and for example ±0.01%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±10%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±5%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±4%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±3%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±2%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±1%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.9%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.8%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.7%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.6%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.5%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.4%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.3%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.2%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.1%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.05%. In some embodiments, "about" indicates deviation from the indicated numerical value by ±0.01%. As will be appreciated by the person of ordinary skill, the specific such deviation for a numerical value for a given technical effect will depend on the nature of the technical effect. For example, a natural or biological technical effect may generally have a larger such deviation than one for a man-made or engineering technical effect.

[0094] Recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein.

[0095] Several documents are cited throughout the text of this specification. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.Definitions

[0096] In the following, definitions will be provided which apply to all aspects of the present disclosure. The following terms have the following meanings unless otherwise indicated. Any undefined terms have their art recognized meanings.

[0097] Terms such as "reduce" or "inhibit" as used herein means the ability to cause an overall decrease, for example, of about 5% or greater, about 10% or greater, about 15% or greater, about 20% or greater, about 25% or greater, about 30% or greater, about 40% or greater, about 50% or greater, or about 75% or greater, in the level. The term "inhibit" or similar phrases includes a complete or essentially complete inhibition, i.e. a reduction to zero or essentially to zero.

[0098] Terms such as "enhance" as used herein means the ability to cause an overall increase, or enhancement, for example, by at least about 5% or greater, about 10% or greater, about 15% or greater, about 20% or greater, about 25% or greater, about 30% or greater, about 40% or greater, about 50% or greater, about 75% or greater, or about 100% or greater in the level.

[0099] "Physiological pH" as used herein refers to a pH of about 7.4. In some embodiments, physiological pH is from 7.3 to 7.5. In some embodiments, physiological pH is from 7.35 to 7.45. In some embodiments, physiological pH is 7.3, 7.35, 7.4, 7.45, or 7.5.

[0100] As used in the present disclosure, "% w / v" refers to weight by volume percent, which is a unit of concentration measuring the amount of solute in grams (g) expressed as a percent of the total volume of solution in milliliters (mL).

[0101] As used in the present disclosure, "% by weight" refers to weight percent, which is a unit of concentration measuring the amount of a substance in grams (g) expressed as a percent of the total weight of the total composition in grams (g).

[0102] As used in the present disclosure, "mol %" is defined as the ratio of the number of moles of one component to the total number of moles of all components, multiplied by 100.

[0103] As used in the present disclosure, "mol % of the total lipid" is defined as the ratio of the number of moles of one lipid component to the total number of moles of all lipids, multiplied by 100. In this context, in some embodiments, the term "total lipid" includes lipids and lipid-like material.

[0104] The term "ionic strength" refers to the mathematical relationship between the number of different kinds of ionic species in a particular solution and their respective charges. Thus, ionic strength I is represented mathematically by the formula: I = 1 2 ⋅ ∑ i z i 2 ⋅ c i

[0105] in which c is the molar concentration of a particular ionic species and z the absolute value of its charge. The sum Σ is taken over all the different kinds of ions (i) in solution.

[0106] According to the disclosure, the term "ionic strength" in some embodiments relates to the presence of monovalent ions. Regarding the presence of divalent ions, in particular divalent cations, their concentration or effective concentration (presence of free ions) due to the presence of chelating agents is, in some embodiments, sufficiently low so as to prevent degradation of the nucleic acid. In some embodiments, the concentration or effective concentration of divalent ions is below the catalytic level for hydrolysis of the phosphodiester bonds between nucleotides such as RNA nucleotides. In some embodiments, the concentration of free divalent ions is 20 µM or less. In some embodiments, there are no or essentially no free divalent ions.

[0107] "Osmolality" refers to the concentration of a particular solute expressed as the number of osmoles of solute per kilogram of solvent.

[0108] The term "lyophilizing" or "lyophilization" refers to the freeze-drying of a substance by freezing it and then reducing the surrounding pressure (e.g., below 15 Pa, such as below 10 Pa, below 5 Pa, or 1 Pa or less) to allow the frozen medium in the substance to sublimate directly from the solid phase to the gas phase. Thus, the terms "lyophilizing" and "freeze-drying" are used herein interchangeably.

[0109] The term "spray-drying" refers to spray-drying a substance by mixing (heated) gas with a fluid that is atomized (sprayed) within a vessel (spray dryer), where the solvent from the formed droplets evaporates, leading to a dry powder.

[0110] The term "reconstitute" relates to adding a solvent such as water to a dried product to return it to a liquid state such as its original liquid state.

[0111] The term "recombinant" in the context of the present disclosure means "made through genetic engineering". In some embodiments, a "recombinant object" in the context of the present disclosure is not occurring naturally.

[0112] The term "naturally occurring" as used herein refers to the fact that an object can be found in nature. For example, a peptide or nucleic acid that is present in an organism (including viruses) and can be isolated from a source in nature and which has not been intentionally modified by man in the laboratory is naturally occurring. The term "found in nature" means "present in nature" and includes known objects as well as objects that have not yet been discovered and / or isolated from nature, but that may be discovered and / or isolated in the future from a natural source.

[0113] As used herein, the terms "room temperature" and "ambient temperature" are used interchangeably herein and refer to temperatures from at least about 15°C, e.g., from about 15°C to about 35°C, from about 15°C to about 30°C, from about 15°C to about 25°C, or from about 17°C to about 22°C. Such temperatures will include 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C and 22°C.

[0114] The term "EDTA" refers to ethylenediaminetetraacetic acid disodium salt. All concentrations are given with respect to the EDTA disodium salt.

[0115] The term "cryoprotectant" relates to a substance that is added to a formulation in order to protect the active ingredients during the freezing stages.

[0116] The term "lyoprotectant" relates to a substance that is added to a formulation in order to protect the active ingredients during the drying stages.

[0117] According to the present disclosure, the term "peptide" refers to substances which comprise about two or more, about 3 or more, about 4 or more, about 6 or more, about 8 or more, about 10 or more, about 13 or more, about 16 or more, about 20 or more, and up to about 50, about 100 or about 150, consecutive amino acids linked to one another via peptide bonds. The term "polypeptide" refers to large peptides, in particular peptides having at least about 151 amino acids. "Peptides" and "polypeptides" are both protein molecules, although the terms "protein" and "polypeptide" are used herein usually as synonyms.

[0118] The term "biological activity" means the response of a biological system to a molecule. Such biological systems may be, for example, a cell or an organism. In some embodiments, such response is therapeutically or pharmaceutically useful.

[0119] The term "portion" refers to a fraction. With respect to a particular structure such as an amino acid sequence or protein the term "portion" thereof may designate a continuous or a discontinuous fraction of said structure.

[0120] The terms "part" and "fragment" are used interchangeably herein and refer to a continuous element. For example, a part of a structure such as an amino acid sequence or protein refers to a continuous element of said structure. When used in context of a composition, the term "part" means a portion of the composition. For example, a part of a composition may be any portion from 0.1% to 99.9% (such as 0.1%, 0.5%, 1%, 5%, 10%, 50%, 90%, or 99%) of said composition.

[0121] "Fragment", with reference to an amino acid sequence (peptide or polypeptide), relates to a part of an amino acid sequence, i.e. a sequence which represents the amino acid sequence shortened at the N-terminus and / or C-terminus. A fragment shortened at the C-terminus (N-terminal fragment) is obtainable, e.g., by translation of a truncated open reading frame that lacks the 3'-end of the open reading frame. A fragment shortened at the N-terminus (C-terminal fragment) is obtainable, e.g., by translation of a truncated open reading frame that lacks the 5'-end of the open reading frame, as long as the truncated open reading frame comprises a start codon that serves to initiate translation. A fragment of an amino acid sequence comprises, e.g., at least 50 %, at least 60 %, at least 70 %, at least 80%, at least 90% of the amino acid residues from an amino acid sequence. A fragment of an amino acid sequence comprises, e.g., at least 6, in particular at least 8, , at least 10, at least 12, at least 15, at least 20, at least 30, at least 50, or at least 100 consecutive amino acids from an amino acid sequence. A fragment of an amino acid sequence comprises, e.g., a sequence of up to 8, in particular up to 10, up to 12, up to 15, up to 20, up to 30 or up to 55, consecutive amino acids of the amino acid sequence.

[0122] "Variant," as used herein and with reference to an amino acid sequence (peptide or polypeptide), is meant an amino acid sequence that differs from a parent amino acid sequence by virtue of at least one amino acid (e.g., a different amino acid, or a modification of the same amino acid). The parent amino acid sequence may be a naturally occurring or wild type (WT) amino acid sequence, or may be a modified version of a wild type amino acid sequence. In some embodiments, the variant amino acid sequence has at least one amino acid difference as compared to the parent amino acid sequence, e.g., from 1 to about 20 amino acid differences, such as from 1 to about 10 or from 1 to about 5 amino acid differences compared to the parent.

[0123] By "wild type" or "WT" or "native" herein is meant an amino acid sequence that is found in nature, including allelic variations. A wild type amino acid sequence, peptide or polypeptide has an amino acid sequence that has not been intentionally modified.

[0124] For the purposes of the present disclosure, "variants" of an amino acid sequence (peptide or polypeptide) may comprise amino acid insertion variants, amino acid addition variants, amino acid deletion variants and / or amino acid substitution variants. The term "variant" includes all mutants, splice variants, post-translationally modified variants, conformations, isoforms, allelic variants, species variants, and species homologs, in particular those which are naturally occurring. The term "variant" includes, in particular, fragments of an amino acid sequence. Amino acid insertion variants comprise insertions of single or two or more amino acids in a particular amino acid sequence. In the case of amino acid sequence variants having an insertion, one or more amino acid residues are inserted into a particular site in an amino acid sequence, although random insertion with appropriate screening of the resulting product is also possible. Amino acid addition variants comprise amino- and / or carboxy-terminal fusions of one or more amino acids, such as 1, 2, 3, 5, 10, 20, 30, 50, or more amino acids. Amino acid deletion variants are characterized by the removal of one or more amino acids from the sequence, such as by removal of 1, 2, 3, 5, 10, 20, 30, 50, or more amino acids. The deletions may be in any position of the protein. Amino acid deletion variants that comprise the deletion at the N-terminal and / or C-terminal end of the protein are also called N-terminal and / or C-terminal truncation variants. Amino acid substitution variants are characterized by at least one residue in the sequence being removed and another residue being inserted in its place. Preference is given to the modifications being in positions in the amino acid sequence which are not conserved between homologous peptides or polypeptides and / or to replacing amino acids with other ones having similar properties. In some embodiments, amino acid changes in peptide and polypeptide variants are conservative amino acid changes, i.e., substitutions of similarly charged or uncharged amino acids. A conservative amino acid change involves substitution of one of a family of amino acids which are related in their side chains. Naturally occurring amino acids are generally divided into four families: acidic (aspartate, glutamate), basic (lysine, arginine, histidine), non-polar (alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan), and uncharged polar (glycine, asparagine, glutamine, cysteine, serine, threonine, tyrosine) amino acids. Phenylalanine, tryptophan, and tyrosine are sometimes classified jointly as aromatic amino acids. In some embodiments, conservative amino acid substitutions include substitutions within the following groups: glycine, alanine; valine, isoleucine, leucine; aspartic acid, glutamic acid; asparagine, glutamine; serine, threonine; lysine, arginine; and phenylalanine, tyrosine.

[0125] In some embodiments the degree of similarity, such as identity between a given amino acid sequence and an amino acid sequence which is a variant of said given amino acid sequence, will be at least about 60%, 70%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%. In some embodiments, the degree of similarity or identity is given for an amino acid region which is at least about 10%, at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90% or about 100% of the entire length of the reference amino acid sequence. For example, if the reference amino acid sequence consists of 200 amino acids, the degree of similarity or identity is given, e.g., for at least about 20, at least about 40, at least about 60, at least about 80, at least about 100, at least about 120, at least about 140, at least about 160, at least about 180, or about 200 amino acids, in some embodiments continuous amino acids. In some embodiments, the degree of similarity or identity is given for the entire length of the reference amino acid sequence. The alignment for determining sequence similarity, such as sequence identity, can be done with art known tools, such as using the best sequence alignment, for example, using Align, using standard settings, preferably EMBOSS::needle, Matrix: Blosum62, Gap Open 10.0, Gap Extend 0.5.

[0126] "Sequence similarity" indicates the percentage of amino acids that either are identical or that represent conservative amino acid substitutions. "Sequence identity" between two amino acid sequences indicates the percentage of amino acids that are identical between the sequences. "Sequence identity" between two nucleic acid sequences indicates the percentage of nucleotides that are identical between the sequences.

[0127] The terms "% identical" and "% identity" or similar terms are intended to refer, in particular, to the percentage of nucleotides or amino acids which are identical in an optimal alignment between the sequences to be compared. Said percentage is purely statistical, and the differences between the two sequences may be but are not necessarily randomly distributed over the entire length of the sequences to be compared. Comparisons of two sequences are usually carried out by comparing the sequences, after optimal alignment, with respect to a segment or "window of comparison", in order to identify local regions of corresponding sequences. The optimal alignment for a comparison may be carried out manually or with the aid of the local homology algorithm by Smith and Waterman, 1981, Ads App. Math. 2, 482, with the aid of the local homology algorithm by Neddleman and Wunsch, 1970, J. Mol. Biol. 48, 443, with the aid of the similarity search algorithm by Pearson and Lipman, 1988, Proc. Natl Acad. Sci. USA 88, 2444, or with the aid of computer programs using said algorithms (GAP, BESTFIT, FASTA, BLAST P, BLAST N and TFASTA in Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Drive, Madison, Wis.). In some embodiments, percent identity of two sequences is determined using the BLASTN or BLASTP algorithm, as available on the United States National Center for Biotechnology Information (NCBI) website (e.g., at blast.ncbi.nim.nih.gov / Blast.cgi?PAGE_TYPE=BlastSearch&BLAST_SPEC=blast2seq&LINK_LOC =align2seq). In some embodiments, the algorithm parameters used for BLASTN algorithm on the NCBI website include: (i) Expect Threshold set to 10; (ii) Word Size set to 28; (iii) Max matches in a query range set to 0; (iv) Match / Mismatch Scores set to 1, -2; (v) Gap Costs set to Linear; and (vi) the filter for low complexity regions being used. In some embodiments, the algorithm parameters used for BLASTP algorithm on the NCBI website include: (i) Expect Threshold set to 10; (ii) Word Size set to 3; (iii) Max matches in a query range set to 0; (iv) Matrix set to BLOSUM62; (v) Gap Costs set to Existence: 11 Extension: 1; and (vi) conditional compositional score matrix adjustment.

[0128] Percentage identity is obtained by determining the number of identical positions at which the sequences to be compared correspond, dividing this number by the number of positions compared (e.g., the number of positions in the reference sequence) and multiplying this result by 100.

[0129] In some embodiments, the degree of similarity or identity is given for a region which is at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90% or about 100% of the entire length of the reference sequence. For example, if the reference nucleic acid sequence consists of 200 nucleotides, the degree of identity is given for at least about 100, at least about 120, at least about 140, at least about 160, at least about 180, or about 200 nucleotides, in some embodiments continuous nucleotides. In some embodiments, the degree of similarity or identity is given for the entire length of the reference sequence. Homologous amino acid sequences exhibit according to the disclosure at least 40%, in particular at least 50%, at least 60%, at least 70%, at least 80%, at least 90% and, e.g., at least 95%, at least 98 or at least 99% identity of the amino acid residues.

[0130] The amino acid sequence variants described herein may readily be prepared by the skilled person, for example, by recombinant DNA manipulation. The manipulation of DNA sequences for preparing peptides or polypeptides having substitutions, additions, insertions or deletions, is described in detail in Molecular Cloning: A Laboratory Manual, 4th Edition, M.R. Green and J. Sambrook eds., Cold Spring Harbor Laboratory Press, Cold Spring Harbor 2012, for example. Furthermore, the peptides, polypeptides and amino acid variants described herein may be readily prepared with the aid of known peptide synthesis techniques such as, for example, by solid phase synthesis and similar methods.

[0131] In some embodiments, a fragment or variant of an amino acid sequence (peptide or polypeptide) is a "functional fragment" or "functional variant". The term "functional fragment" or "functional variant" of an amino acid sequence relates to any fragment or variant exhibiting one or more functional properties identical or similar to those of the amino acid sequence from which it is derived, i.e., it is functionally equivalent. With respect to antigens or antigenic sequences, one particular function is one or more immunogenic activities displayed by the amino acid sequence from which the fragment or variant is derived. The term "functional fragment" or "functional variant", as used herein, in particular refers to a variant molecule or sequence that comprises an amino acid sequence that is altered by one or more amino acids compared to the amino acid sequence of the parent molecule or sequence and that is still capable of fulfilling one or more of the functions of the parent molecule or sequence, e.g., inducing an immune response. In some embodiments, the modifications in the amino acid sequence of the parent molecule or sequence do not significantly affect or alter the characteristics of the molecule or sequence. In different embodiments, the function of the functional fragment or functional variant may be reduced but still significantly present, e.g., function of the functional fragment or functional variant may be at least 50%, at least 60%, at least 70%, at least 80%, or at least 90% of the parent molecule or sequence. However, in other embodiments, function of the functional fragment or functional variant may be enhanced compared to the parent molecule or sequence.

[0132] An amino acid sequence (peptide or polypeptide) "derived from" a designated amino acid sequence (peptide or polypeptide) refers to the origin of the first amino acid sequence. In some embodiments, the amino acid sequence which is derived from a particular amino acid sequence has an amino acid sequence that is identical, essentially identical or homologous to that particular sequence or a fragment thereof. Amino acid sequences derived from a particular amino acid sequence may be variants of that particular sequence or a fragment thereof. For example, it will be understood by one of ordinary skill in the art that the antigens suitable for use herein may be altered such that they vary in sequence from the naturally occurring or native sequences from which they were derived, while retaining the desirable activity of the native sequences.

[0133] In some embodiments, "isolated" means removed (e.g., purified) from the natural state or from an artificial composition, such as a composition from a production process. For example, a nucleic acid, peptide or polypeptide naturally present in a living animal is not "isolated", but the same nucleic acid, peptide or polypeptide partially or completely separated from the coexisting materials of its natural state is "isolated". An isolated nucleic acid, peptide or polypeptide can exist in substantially purified form, or can exist in a non-native environment such as, for example, a host cell.

[0134] The term "transfection" relates to the introduction of nucleic acids, in particular RNA, into a cell. For purposes of the present disclosure, the term "transfection" also includes the introduction of a nucleic acid into a cell or the uptake of a nucleic acid by such cell, wherein the cell may be present in a subject, e.g., a patient, or the cell may be in vitro, e.g., outside of a patient. Thus, according to the present disclosure, a cell for transfection of a nucleic acid described herein can be present in vitro or in vivo, e.g. the cell can form part of an organ, a tissue and / or the body of a patient. According to the disclosure, transfection can be transient or stable. For some applications of transfection, it is sufficient if the transfected genetic material is only transiently expressed. RNA can be transfected into cells to transiently express its coded protein. Since the nucleic acid introduced in the transfection process is usually not integrated into the nuclear genome, the foreign nucleic acid will be diluted through mitosis or degraded. Cells allowing episomal amplification of nucleic acids greatly reduce the rate of dilution. If it is desired that the transfected nucleic acid actually remains in the genome of the cell and its daughter cells, a stable transfection must occur. Such stable transfection can be achieved by using virus-based systems or transposon-based systems for transfection, for example. Generally, nucleic acid encoding antigen is transiently transfected into cells. RNA can be transfected into cells to transiently express its coded protein.

[0135] The disclosure includes analogs of a peptide or polypeptide. According to the present disclosure, an analog of a peptide or polypeptide is a modified form of said peptide or polypeptide from which it has been derived and has at least one functional property of said peptide or polypeptide. E.g., a pharmacological active analog of a peptide or polypeptide has at least one of the pharmacological activities of the peptide or polypeptide from which the analog has been derived. Such modifications include any chemical modification and comprise single or multiple substitutions, deletions and / or additions of any molecules associated with the peptide or polypeptide, such as carbohydrates, lipids and / or peptides or polypeptides. In some embodiments, "analogs" of peptides or polypeptides include those modified forms resulting from glycosylation, acetylation, phosphorylation, amidation, palmitoylation, myristoylation, isoprenylation, lipidation, alkylation, derivatization, introduction of protective / blocking groups, proteolytic cleavage or binding to an antibody or to another cellular ligand. The term "analog" also extends to all functional chemical equivalents of said peptides and polypeptides.

[0136] As used herein, the terms "linked", "fused", or "fusion" are used interchangeably. These terms refer to the joining together of two or more elements or components or domains.

[0137] As used herein "endogenous" refers to any material from or produced inside an organism, cell, tissue or system.

[0138] As used herein, the term "exogenous" refers to any material introduced from or produced outside an organism, cell, tissue or system.

[0139] According to various embodiments of the present disclosure, a nucleic acid such as RNA encoding a peptide or polypeptide is taken up by or introduced, i.e. transfected or transduced, into a cell which cell may be present in vitro or in a subject, resulting in expression of said peptide or polypeptide. The cell may, e.g., express the encoded peptide or polypeptide intracellularly (e.g. in the cytoplasm and / or in the nucleus), may secrete the encoded peptide or polypeptide, and / or may express it on the surface.

[0140] According to the present disclosure, terms such as "nucleic acid expressing" and "nucleic acid encoding" or similar terms are used interchangeably herein and with respect to a particular peptide or polypeptide mean that the nucleic acid, if present in the appropriate environment, e.g. within a cell, can be expressed to produce said peptide or polypeptide.

[0141] The term "expression" as used herein includes the transcription and / or translation of a particular nucleotide sequence.

[0142] In the context of the present disclosure, the term "transcription" relates to a process, wherein the genetic code in a DNA sequence is transcribed into RNA (especially mRNA). Subsequently, the RNA may be translated into peptide or polypeptide.

[0143] With respect to RNA, the term "expression" or "translation" relates to the process in the ribosomes of a cell by which a strand of mRNA directs the assembly of a sequence of amino acids to make a peptide or polypeptide.

[0144] A medical preparation, in particular kit, described herein may comprise instructional material or instructions. As used herein, "instructional material" or "instructions" includes a publication, a recording, a diagram, or any other medium of expression which can be used to communicate the usefulness of the compositions and methods of the present disclosure. The instructional material of the kit of the present disclosure may, for example, be affixed to a container which contains the compositions / formulations of the present disclosure or be shipped together with a container which contains the compositions / formulations. Alternatively, the instructional material may be shipped separately from the container with the intention that the instructional material and the compositions be used cooperatively by the recipient.

[0145] Prodrugs of a particular compound described herein are those compounds that upon administration to an individual undergo chemical conversion under physiological conditions to provide the particular compound. Additionally, prodrugs can be converted to the particular compound by chemical or biochemical methods in an ex vivo environment. For example, prodrugs can be slowly converted to the particular compound when, for example, placed in a transdermal patch reservoir with a suitable enzyme or chemical reagent. Exemplary prodrugs are esters (using an alcohol or a carboxy group contained in the particular compound) or amides (using an amino or a carboxy group contained in the particular compound) which are hydrolyzable in vivo. Specifically, any amino group which is contained in the particular compound and which bears at least one hydrogen atom can be converted into a prodrug form. Typical N-prodrug forms include carbamates, Mannich bases, enamines, and enaminones.

[0146] In the present specification, a structural formula of a compound may represent a certain isomer of said compound. It is to be understood, however, that the present disclosure includes all isomers such as geometrical isomers, optical isomers based on an asymmetrical carbon, stereoisomers, tautomers and the like which occur structurally and isomer mixtures and is not limited to the description of the formula. Furthermore, in the present specification, a structural formula of a compound may represent a specific salt and / or solvate of said compound. It is to be understood, however, that the present disclosure includes all salts (e.g., pharmaceutically acceptable salts) and solvates (e.g., hydrates) and is not limited to the description of the specific salt and / or solvate.

[0147] "Isomers" are compounds having the same molecular formula but differ in structure ("structural isomers") or in the geometrical (spatial) positioning of the functional groups and / or atoms ("stereoisomers"). "Enantiomers" are a pair of stereoisomers which are non-superimposable mirror-images of each other. A "racemic mixture" or "racemate" contains a pair of enantiomers in equal amounts and is denoted by the prefix (±). "Diastereomers" are stereoisomers which are non-superimposable and which are not mirror-images of each other. "Tautomers" are structural isomers of the same chemical substance that spontaneously and reversibly interconvert into each other, even when pure, due to the migration of individual atoms or groups of atoms; i.e., the tautomers are in a dynamic chemical equilibrium with each other. An example of tautomers are the isomers of the keto-enol-tautomerism. "Conformers" are stereoisomers that can be interconverted just by rotations about formally single bonds, and include - in particular - those leading to different 3-dimentional forms of (hetero)cyclic rings, such as chair, half-chair, boat, and twist-boat forms of cyclohexane.

[0148] The term "solvate" as used herein refers to an addition complex of a dissolved material in a solvent (such as an organic solvent (e.g., an aliphatic alcohol (such as methanol, ethanol, n-propanol, isopropanol), acetone, acetonitrile, ether, and the like), water or a mixture of two or more of these liquids), wherein the addition complex exists in the form of a crystal or mixed crystal. The amount of solvent contained in the addition complex may be stoichiometric or non-stoichiometric. A "hydrate" is a solvate wherein the solvent is water.

[0149] In isotopically labeled compounds one or more atoms are replaced by a corresponding atom having the same number of protons but differing in the number of neutrons. For example, a hydrogen atom may be replaced by a deuterium or tritium atom. Exemplary isotopes which can be used in the present disclosure include deuterium, tritium, 11< C, 13< C, 14< C, 15< N, 18< F, 32< P, 32< S, 35< S, 36< Cl, and 125< I.

[0150] The term "average diameter" refers to the mean hydrodynamic diameter of particles as measured by dynamic light scattering (DLS) with data analysis using the so-called cumulant algorithm, which provides as results the so-called Z average with the dimension of a length, and the polydispersity index (PDI), which is dimensionless (Koppel, D., J. Chem. Phys. 57, 1972, pp 4814-4820, ISO 13321). Here "average diameter", "diameter" or "size" for particles is used synonymously with this value of the Z average .

[0151] In some embodiments, the "polydispersity index" is calculated based on dynamic light scattering measurements by the so-called cumulant analysis as mentioned in the definition of the "average diameter". Under certain prerequisites, it can be taken as a measure of the size distribution of an ensemble of nanoparticles.

[0152] The "radius of gyration" (abbreviated herein as R g ) of a particle about an axis of rotation is the radial distance of a point from the axis of rotation at which, if the whole mass of the particle is assumed to be concentrated, its moment of inertia about the given axis would be the same as with its actual distribution of mass. Mathematically, R g is the root mean square distance of the particle's components from either its center of mass or a given axis. For example, for a macromolecule composed of n mass elements, of masses m i (i = 1, 2, 3, ..., n), located at fixed distances s i from the center of mass, R g is the square-root of the mass average of s i 2< over all mass elements and can be calculated as follows: R g = ∑ i = 1 n m i ⋅ s i 2 / ∑ i = 1 n m i 1 / 2

[0153] The radius of gyration can be determined or calculated experimentally, e.g., by using light scattering. In particular, for small scattering vectors q the structure function S is defined as follows: S q → ≈ N ⋅ 1 − q 2 ⋅ R g 2 3 wherein N is the number of components (Guinier's law).

[0154] The "hydrodynamic radius" (which is sometimes called "Stokes radius" or "Stokes-Einstein radius") of a particle is the radius of a hypothetical hard sphere that diffuses at the same rate as said particle. The hydrodynamic radius is related to the mobility of the particle, taking into account not only size but also solvent effects. For example, a smaller charged particle with stronger hydration may have a greater hydrodynamic radius than a larger charged particle with weaker hydration. This is because the smaller particle drags a greater number of water molecules with it as it moves through the solution. Since the actual dimensions of the particle in a solvent are not directly measurable, the hydrodynamic radius may be defined by the Stokes-Einstein equation: R h = k B ⋅ T 6 ⋅ π ⋅ η ⋅ D wherein k B is the Boltzmann constant; T is the temperature; η is the viscosity of the solvent; and D is the diffusion coefficient. The diffusion coefficient can be determined experimentally, e.g., by using dynamic light scattering (DLS). Thus, one procedure to determine the hydrodynamic radius of a particle or a population of particles (such as the hydrodynamic radius of particles contained in a sample or control composition as disclosed herein or the hydrodynamic radius of a particle peak obtained from subjecting such a sample or control composition to field-flow fractionation) is to measure the DLS signal of said particle or population of particles (such as DLS signal of particles contained in a sample or control composition as disclosed herein or the DLS signal of a particle peak obtained from subjecting such a sample or control composition to field-flow fractionation).

[0155] The expression "light scattering" as used herein refers to the physical process where light is forced to deviate from a straight trajectory by one or more paths due to localized nonuniformities in the medium through which the light passes.

[0156] The term "UV" means ultraviolet and designates a band of the electromagnetic spectrum with a wavelength from 10 nm to 400 nm, i.e., shorter than that of visible light but longer than X-rays.

[0157] The expression "multi-angle light scattering" or "MALS" as used herein relates to a technique for measuring the light scattered by a sample into a plurality of angles. "Multi-angle" means in this respect that scattered light can be detected at different discrete angles as measured, for example, by a single detector moved over a range including the specific angles selected or an array of detectors fixed at specific angular locations. In certain embodiments, the light source used in MALS is a laser source (MALLS: multi-angle laser light scattering). Based on the MALS signal of a composition comprising particles and by using an appropriate formalism (e.g., Zimm plot, Berry plot, or Debye plot), it is possible to determine the radius of gyration (R g ) and, thus, the size of said particles. Preferably, the Zimm plot is a graphical presentation using the following equation: R θ K * c = M w P θ − 2 A 2 cM w 2 P 2 θ wherein c is the mass concentration of the particles in the solvent (g / mL); A 2 is the second virial coefficient (mol·mL / g 2< ); P(ϑ) is a form factor relating to the dependence of scattered light intensity on angle; R ϑ is the excess Rayleigh ratio (cm -1< ); and K* is an optical constant that is equal to 4π 2< η o (dn / dc) 2< λ 0 -4< N A -1< , where η o is the refractive index of the solvent at the incident radiation (vacuum) wavelength, λ 0 is the incident radiation (vacuum) wavelength (nm), N A is Avogadro's number (mol -1< ), and dn / dc is the differential refractive index increment (mL / g) (cf., e.g., Buchholz et al. (Electrophoresis 22 (2001), 4118-4128); B.H. Zimm (J. Chem. Phys. 13 (1945), 141; P. Debye (J. Appl. Phys. 15 (1944): 338; and W. Burchard (Anal. Chem. 75 (2003), 4279-4291). Preferably, the Berry plot is calculated using the following term or the reciprocal thereof: R θ K * c wherein c, R ϑ and K* are as defined above. Preferably, the Debye plot is calculated using the following term or the reciprocal thereof: K * c R θ wherein c, R ϑ and K* are as defined above.

[0158] The expression "dynamic light scattering" or "DLS" as used herein refers to a technique to determine the size and size distribution profile of particles, in particular with respect to the hydrodynamic radius of the particles. A monochromatic light source, usually a laser, is shot through a polarizer and into a sample. The scattered light then goes through a second polarizer where it is detected and the resulting image is projected onto a screen. The particles in the solution are being hit with the light and diffract the light in all directions. The diffracted light from the particles can either interfere constructively (light regions) or destructively (dark regions). This process is repeated at short time intervals and the resulting set of speckle patterns are analyzed by an autocorrelator that compares the intensity of light at each spot over time.

[0159] The expression "static light scattering" or "SLS" as used herein refers to a technique to determine the size and size distribution profile of particles, in particular with respect to the radius of gyration of the particles, and / or the molar mass of particles. A high-intensity monochromatic light, usually a laser, is launched in a solution containing the particles. One or many detectors are used to measure the scattering intensity at one or many angles. The angular dependence is needed to obtain accurate measurements of both molar mass and size for all macromolecules of radius. Hence simultaneous measurements at several angles relative to the direction of incident light, known as multi-angle light scattering (MALS) or multi-angle laser light scattering (MALLS), is generally regarded as the standard implementation of static light scattering.Nucleic Acids

[0160] The term "nucleic acid" comprises deoxyribonucleic acid (DNA), ribonucleic acid (RNA), combinations thereof, and modified forms thereof. The term comprises genomic DNA, cDNA, mRNA, recombinantly produced and chemically synthesized molecules. In some embodiments, a nucleic acid is DNA. In some embodiments, a nucleic acid is RNA. In some embodiments, a nucleic acid is a mixture of DNA and RNA. A nucleic acid may be present as a single-stranded or double-stranded and linear or covalently circularly closed molecule. A nucleic acid can be isolated. The term "isolated nucleic acid" means, according to the present disclosure, that the nucleic acid (i) was amplified in vitro, for example via polymerase chain reaction (PCR) for DNA or in vitro transcription (using, e.g., an RNA polymerase) for RNA, (ii) was produced recombinantly by cloning, (iii) was purified, for example, by cleavage and separation by gel electrophoresis, or (iv) was synthesized, for example, by chemical synthesis. The term "nucleoside" (abbreviated herein as "N") relates to compounds which can be thought of as nucleotides without a phosphate group. While a nucleoside is a nucleobase linked to a sugar (e.g., ribose or deoxyribose), a nucleotide is composed of a nucleoside and one or more phosphate groups. Examples of nucleosides include cytidine, uridine, pseudouridine, adenosine, and guanosine.

[0161] The five standard nucleosides which usually make up naturally occurring nucleic acids are uridine, adenosine, thymidine, cytidine and guanosine. The five nucleosides are commonly abbreviated to their one letter codes U, A, T, C and G, respectively. However, thymidine is more commonly written as "dT" ("d" represents "deoxy") as it contains a 2'-deoxyribofuranose moiety rather than the ribofuranose ring found in uridine. This is because thymidine is found in deoxyribonucleic acid (DNA) and not ribonucleic acid (RNA). Conversely, uridine is found in RNA and not DNA. The remaining three nucleosides may be found in both RNA and DNA. In RNA, they would be represented as A, C and G, whereas in DNA they would be represented as dA, dC and dG.

[0162] A modified purine (A or G) or pyrimidine (C, T, or U) base moiety is, in some embodiments, modified by one or more alkyl groups, e.g., one or more C 1-4 alkyl groups, e.g., one or more methyl groups. Particular examples of modified purine or pyrimidine base moieties include N 7< -alkyl-guanine, N 6< -alkyl-adenine, 5-alkyl-cytosine, 5-alkyl-uracil, and N(1)-alkyl-uracil, such as N 7< -C 1-4 alkyl-guanine, N 6< -C 1-4 alkyl-adenine, 5-C 1-4 alkyl-cytosine, 5-C 1-4 alkyl-uracil, and N(1)-C 14 alkyl-uracil, preferably N 7< -methyl-guanine, N 6< -methyl-adenine, 5-methyl-cytosine, 5-methyl-uracil, and N(1)-methyl-uracil.

[0163] Herein, the term "DNA" relates to a nucleic acid molecule which includes deoxyribonucleotide residues. In preferred embodiments, the DNA contains all or a majority of deoxyribonucleotide residues. As used herein, "deoxyribonucleotide" refers to a nucleotide which lacks a hydroxyl group at the 2'-position of a β-D-ribofuranosyl group. DNA encompasses without limitation, double stranded DNA, single stranded DNA, isolated DNA such as partially purified DNA, essentially pure DNA, synthetic DNA, recombinantly produced DNA, as well as modified DNA that differs from naturally occurring DNA by the addition, deletion, substitution and / or alteration of one or more nucleotides. Such alterations may refer to addition of non-nucleotide material to internal DNA nucleotides or to the end(s) of DNA. It is also contemplated herein that nucleotides in DNA may be non-standard nucleotides, such as chemically synthesized nucleotides or ribonucleotides. For the present disclosure, these altered DNAs are considered analogs of naturally-occurring DNA. A molecule contains "a majority of deoxyribonucleotide residues" if the content of deoxyribonucleotide residues in the molecule is more than 50% (such as at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%), based on the total number of nucleotide residues in the molecule. The total number of nucleotide residues in a molecule is the sum of all nucleotide residues (irrespective of whether the nucleotide residues are standard (i.e., naturally occurring) nucleotide residues or analogs thereof).

[0164] DNA may be recombinant DNA and may be obtained by cloning of a nucleic acid, in particular cDNA. The cDNA may be obtained by reverse transcription of RNA.

[0165] The term "RNA" relates to a nucleic acid molecule which includes ribonucleotide residues. In preferred embodiments, the RNA contains all or a majority of ribonucleotide residues. As used herein, "ribonucleotide" refers to a nucleotide with a hydroxyl group at the 2'-position of a β-D-ribofuranosyl group. RNA encompasses without limitation, double stranded RNA, single stranded RNA, isolated RNA such as partially purified RNA, essentially pure RNA, synthetic RNA, recombinantly produced RNA, as well as modified RNA that differs from naturally occurring RNA by the addition, deletion, substitution and / or alteration of one or more nucleotides. Such alterations may refer to addition of non-nucleotide material to internal RNA nucleotides or to the end(s) of RNA. It is also contemplated herein that nucleotides in RNA may be non-standard nucleotides, such as chemically synthesized nucleotides or deoxynucleotides. For the present disclosure, these altered / modified nucleotides can be referred to as analogs of naturally occurring nucleotides, and the corresponding RNAs containing such altered / modified nucleotides (i.e., altered / modified RNAs) can be referred to as analogs of naturally occurring RNAs. A molecule contains "a majority of ribonucleotide residues" if the content of ribonucleotide residues in the molecule is more than 50% (such as at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%), based on the total number of nucleotide residues in the molecule. The total number of nucleotide residues in a molecule is the sum of all nucleotide residues (irrespective of whether the nucleotide residues are standard (i.e., naturally occurring) nucleotide residues or analogs thereof). "RNA" includes mRNA, tRNA, ribosomal RNA (rRNA), small nuclear RNA (snRNA), self-amplifying RNA (saRNA), single-stranded RNA (ssRNA), dsRNA, inhibitory RNA (such as antisense ssRNA, small interfering RNA (siRNA), or microRNA (miRNA)), activating RNA (such as small activating RNA) and immunostimulatory RNA (isRNA). In some embodiments, "RNA" refers to mRNA.

[0166] The term "in vitro transcription" or "IVT" as used herein means that the transcription (i.e., the generation of RNA) is conducted in a cell-free manner. I.e., IVT does not use living / cultured cells but rather the transcription machinery extracted from cells (e.g., cell lysates or the isolated components thereof, including an RNA polymerase (preferably T7, T3 or SP6 polymerase)).mRNA

[0167] According to the present disclosure, the term "mRNA" means "messenger-RNA" and includes a "transcript" which may be generated by using a DNA template. Generally, mRNA encodes a peptide or polypeptide.

[0168] mRNA is single-stranded but may contain self-complementary sequences that allow parts of the mRNA to fold and pair with itself to form double helices.

[0169] According to the present disclosure, "dsRNA" means double-stranded RNA and is RNA with two partially or completely complementary strands.

[0170] In preferred embodiments of the present disclosure, the mRNA relates to an RNA transcript which encodes a peptide or polypeptide.

[0171] In some embodiments, the mRNA which preferably encodes a peptide or polypeptide has a length of at least 45 nucleotides (such as at least 60, at least 90, at least 100, at least 200, at least 300, at least 400, at least 500, at least 600, at least 700, at least 800, at least 900, at least 1,000, at least 1,500, at least 2,000, at least 2,500, at least 3,000, at least 3,500, at least 4,000, at least 4,500, at least 5,000, at least 6,000, at least 7,000, at least 8,000, at least 9,000 nucleotides), preferably up to 15,000, such as up to 14,000, up to 13,000, up to 12,000 nucleotides, up to 11,000 nucleotides or up to 10,000 nucleotides.

[0172] As established in the art, mRNA generally contains a 5' untranslated region (5'-UTR), a peptide / polypeptide coding region and a 3' untranslated region (3'-UTR). In some embodiments, the mRNA is produced by in vitro transcription or chemical synthesis. In some embodiments, the mRNA is produced by in vitro transcription using a DNA template. The in vitro transcription methodology is known to the skilled person; cf., e.g., Molecular Cloning: A Laboratory Manual, 4th Edition, M.R. Green and J. Sambrook eds., Cold Spring Harbor Laboratory Press, Cold Spring Harbor 2012. Furthermore, a variety of in vitro transcription kits is commercially available, e.g., from Thermo Fisher Scientific (such as TranscriptAid ™< T7 kit, MEGAscript ®< T7 kit, MAXIscript ®< ), New England BioLabs Inc. (such as HiScribe ™< T7 kit, HiScribe ™< T7 ARCA mRNA kit), Promega (such as RiboMAX ™< , HeLaScribe ®< , Riboprobe ®< systems), Jena Bioscience (such as SP6 or T7 transcription kits), and Epicentre (such as AmpliScribe ™< ). For providing modified mRNA, correspondingly modified nucleotides, such as modified naturally occurring nucleotides, non-naturally occurring nucleotides and / or modified non-naturally occurring nucleotides, can be incorporated during synthesis (preferably in vitro transcription), or modifications can be effected in and / or added to the mRNA after transcription.

[0173] In some embodiments, mRNA is in vitro transcribed mRNA (IVT-RNA) and may be obtained by in vitro transcription of an appropriate DNA template. The promoter for controlling transcription can be any promoter for any RNA polymerase. Particular examples of RNA polymerases are the T7, T3, and SP6 RNA polymerases. Preferably, the in vitro transcription is controlled by a T7 or SP6 promoter. A DNA template for in vitro transcription may be obtained by cloning of a nucleic acid, in particular cDNA, and introducing it into an appropriate vector for in vitro transcription. The cDNA may be obtained by reverse transcription of RNA.

[0174] In some embodiments of the present disclosure, the mRNA is "replicon mRNA" or simply a "replicon", in particular "self-replicating mRNA" or "self-amplifying mRNA". In certain embodiments, the replicon or self-replicating mRNA is derived from or comprises elements derived from an ssRNA virus, in particular a positive-stranded ssRNA virus such as an alphavirus. Alphaviruses are typical representatives of positive-stranded RNA viruses. Alphaviruses replicate in the cytoplasm of infected cells (for review of the alphaviral life cycle see José et al., Future Microbiol., 2009, vol. 4, pp. 837-856). The total genome length of many alphaviruses typically ranges between 11,000 and 12,000 nucleotides, and the genomic RNA typically has a 5'-cap, and a 3' poly(A) tail. The genome of alphaviruses encodes non-structural proteins (involved in transcription, modification and replication of viral RNA and in protein modification) and structural proteins (forming the virus particle). There are typically two open reading frames (ORFs) in the genome. The four non-structural proteins (nsP1-nsP4) are typically encoded together by a first ORF beginning near the 5' terminus of the genome, while alphavirus structural proteins are encoded together by a second ORF which is found downstream of the first ORF and extends near the 3' terminus of the genome. Typically, the first ORF is larger than the second ORF, the ratio being roughly 2:1. In cells infected by an alphavirus, only the nucleic acid sequence encoding non-structural proteins is translated from the genomic RNA, while the genetic information encoding structural proteins is translatable from a subgenomic transcript, which is an RNA molecule that resembles eukaryotic messenger RNA (mRNA; Gould et al., 2010, Antiviral Res., vol. 87 pp. 111-124). Following infection, i.e. at early stages of the viral life cycle, the (+) stranded genomic RNA directly acts like a messenger RNA for the translation of the open reading frame encoding the non-structural poly-protein (nsP1234). Alphavirus-derived vectors have been proposed for delivery of foreign genetic information into target cells or target organisms. In simple approaches, the open reading frame encoding alphaviral structural proteins is replaced by an open reading frame encoding a protein of interest. Alphavirus-based trans-replication systems rely on alphavirus nucleotide sequence elements on two separate nucleic acid molecules: one nucleic acid molecule encodes a viral replicase, and the other nucleic acid molecule is capable of being replicated by said replicase in trans (hence the designation trans-replication system). Trans-replication requires the presence of both these nucleic acid molecules in a given host cell. The nucleic acid molecule capable of being replicated by the replicase in trans must comprise certain alphaviral sequence elements to allow recognition and RNA synthesis by the alphaviral replicase.

[0175] In some embodiments of the present disclosure, the RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) contains one or more modifications, e.g., in order to increase its stability and / or increase translation efficiency and / or decrease immunogenicity and / or decrease cytotoxicity. For example, in order to increase expression of the RNA (in particular, mRNA), it may be modified within the coding region, i.e., the sequence encoding the expressed peptide or polypeptide, preferably without altering the sequence of the expressed peptide or polypeptide. Such modifications are described, for example, in WO 2007 / 036366 and PCT / EP2019 / 056502, and include the following: a 5'-cap structure; an extension or truncation of the naturally occurring poly(A) tail; an alteration of the 5'- and / or 3'-untranslated regions (UTR) such as introduction of a UTR which is not related to the coding region of said RNA; the replacement of one or more naturally occurring nucleotides with synthetic nucleotides; and codon optimization (e.g., to alter, preferably increase, the GC content of the RNA).

[0176] In some embodiments, the RNA (in particular, mRNA) described herein comprises a 5'-cap structure. In some embodiments, the mRNA does not have uncapped 5'-triphosphates. In some embodiments, the RNA (in particular, mRNA)may comprise a conventional 5'-cap and / or a 5'-cap analog. The term "conventional 5'-cap" refers to a cap structure found on the 5'-end of an mRNA molecule and generally consists of a guanosine 5'-triphosphate (Gppp) which is connected via its triphosphate moiety to the 5'-end of the next nucleotide of the mRNA (i.e., the guanosine is connected via a 5' to 5' triphosphate linkage to the rest of the mRNA). The guanosine may be methylated at position N 7< (resulting in the cap structure m 7< Gppp). The term "5'-cap analog" includes a 5'-cap which is based on a conventional 5'-cap but which has been modified at either the 2'- or 3'-position of the m 7< guanosine structure in order to avoid an integration of the 5'-cap analog in the reverse orientation (such 5'-cap analogs are also called anti-reverse cap analogs (ARCAs)). Particularly preferred 5'-cap analogs are those having one or more substitutions at the bridging and non-bridging oxygen in the phosphate bridge, such as phosphorothioate modified 5'-cap analogs at the β-phosphate (such as m 2 7,2'O< G(5')ppSp(5')G (referred to as beta-S-ARCA or β-S-ARCA)), as described in PCT / EP2019 / 056502. Providing an RNA (in particular, mRNA)with a 5'-cap structure as described herein may be achieved by in vitro transcription of a DNA template in presence of a corresponding 5'-cap compound, wherein said 5'-cap structure is co-transcriptionally incorporated into the generated RNA (in particular, mRNA) strand, or the RNA (in particular, mRNA) may be generated, for example, by in vitro transcription, and the 5'-cap structure may be attached to the RNA post-transcriptionally using capping enzymes, for example, capping enzymes of vaccinia virus.

[0177] In some embodiments, the RNA (in particular, mRNA) comprises a 5'-cap structure selected from the group consisting of m 2 7,2'O< G(5')ppSp(5')G (in particular its D1 diastereomer), m 2 7,3'O< G(5')ppp(5')G, and m 2 7,3'O< Gppp(m 1 2'-O< )ApG. In some embodiments, RNA encoding a peptide or polypeptide comprising an antigen or epitope comprises m 2 7,2'O< G(5')ppSp(5')G (in particular its D1 diastereomer) as 5'-cap structure.

[0178] In some embodiments, the RNA (in particular, mRNA) comprises a cap0, cap1, or cap2, preferably cap1 or cap2. According to the present disclosure, the term "cap0" means the structure "m 7< GpppN", wherein N is any nucleoside bearing an OH moiety at position 2'. According to the present disclosure, the term "cap1" means the structure "m 7< GpppNm", wherein Nm is any nucleoside bearing an OCH 3 moiety at position 2'. According to the present disclosure, the term "cap2" means the structure "m 7< GpppNmNm", wherein each Nm is independently any nucleoside bearing an OCH 3 moiety at position 2'.

[0179] The 5'-cap analog beta-S-ARCA (β-S-ARCA) has the following structure:

[0180] The "D1 diastereomer of beta-S-ARCA" or "beta-S-ARCA(D1)" is the diastereomer of beta-S-ARCA which elutes first on an HPLC column compared to the D2 diastereomer of beta-S-ARCA (beta-S-ARCA(D2)) and thus exhibits a shorter retention time. The HPLC preferably is an analytical HPLC. In some embodiments, a Supelcosil LC-18-T RP column, preferably of the format: 5 µm, 4.6 x 250 mm is used for separation, whereby a flow rate of 1.3 ml / min can be applied. In some embodiments, a gradient of methanol in ammonium acetate, for example, a 0-25% linear gradient of methanol in 0.05 M ammonium acetate, pH = 5.9, within 15 min is used. UV-detection (VWD) can be performed at 260 nm and fluorescence detection (FLD) can be performed with excitation at 280 nm and detection at 337 nm.

[0181] The 5'-cap analog m 2 7,3'-O< Gppp(m 1 2'-O< )ApG (also referred to as m 2 7,3'O< G(5')ppp(5')m 2'-O< ApG) which is a building block of a cap1 has the following structure:

[0182] An exemplary cap0 mRNA comprising β-S-ARCA and mRNA has the following structure:

[0183] An exemplary cap0 mRNA comprising m 2 7,3'O< G(5')ppp(5')G and mRNA has the following structure:

[0184] An exemplary cap1 mRNA comprising m 2 7,3'-O< Gppp(m 1 2'-O< )ApG and mRNA has the following structure:

[0185] As used herein, the term "poly-A tail" or "poly-A sequence" refers to an uninterrupted or interrupted sequence of adenylate residues which is typically located at the 3'-end of an mRNA molecule. Poly-A tails or poly-A sequences are known to those of skill in the art and may follow the 3'-UTR in the RNAs (in particular, mRNAs) described herein. An uninterrupted poly-A tail is characterized by consecutive adenylate residues. In nature, an uninterrupted poly-A tail is typical. RNAs (in particular, mRNAs) disclosed herein can have a poly-A tail attached to the free 3'-end of the RNA by a template-independent RNA polymerase after transcription or a poly-A tail encoded by DNA and transcribed by a template-dependent RNA polymerase.

[0186] It has been demonstrated that a poly-A tail of about 120 A nucleotides has a beneficial influence on the levels of mRNA in transfected eukaryotic cells, as well as on the levels of protein that is translated from an open reading frame that is present upstream (5') of the poly-A tail (Holtkamp et al., 2006, Blood, vol. 108, pp. 4009-4017).

[0187] The poly-A tail may be of any length. In some embodiments, a poly-A tail comprises, essentially consists of, or consists of at least 20, at least 30, at least 40, at least 80, or at least 100 and up to 500, up to 400, up to 300, up to 200, or up to 150 A nucleotides, and, in particular, about 120 A nucleotides. In this context, "essentially consists of" means that most nucleotides in the poly-A tail, typically at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% by number of nucleotides in the poly-A tail are A nucleotides, but permits that remaining nucleotides are nucleotides other than A nucleotides, such as U nucleotides (uridylate), G nucleotides (guanylate), or C nucleotides (cytidylate). In this context, "consists of" means that all nucleotides in the poly-A tail, i.e., 100% by number of nucleotides in the poly-A tail, are A nucleotides. The term "A nucleotide" or "A" refers to adenylate.

[0188] In some embodiments, a poly-A tail is attached during RNA transcription, e.g., during preparation of in vitro transcribed RNA, based on a DNA template comprising repeated dT nucleotides (deoxythymidylate) in the strand complementary to the coding strand. The DNA sequence encoding a poly-A tail (coding strand) is referred to as poly(A) cassette.

[0189] In some embodiments, the poly(A) cassette present in the coding strand of DNA essentially consists of dA nucleotides, but is interrupted by a random sequence of the four nucleotides (dA, dC, dG, and dT). Such random sequence may be 5 to 50, 10 to 30, or 10 to 20 nucleotides in length. Such a cassette is disclosed in WO 2016 / 005324.

[0190] Any poly(A) cassette disclosed in WO 2016 / 005324 A1 may be used in the present disclosure. A poly(A) cassette that essentially consists of dA nucleotides, but is interrupted by a random sequence having an equal distribution of the four nucleotides (dA, dC, dG, dT) and having a length of e.g., 5 to 50 nucleotides shows, on DNA level, constant propagation of plasmid DNA in E. coli and is still associated, on RNA level, with the beneficial properties with respect to supporting RNA stability and translational efficiency is encompassed. Consequently, in some embodiments, the poly-A tail contained in an RNA (in particular, mRNA) molecule described herein essentially consists of A nucleotides, but is interrupted by a random sequence of the four nucleotides (A, C, G, U). Such random sequence may be 5 to 50, 10 to 30, or 10 to 20 nucleotides in length.

[0191] In some embodiments, no nucleotides other than A nucleotides flank a poly-A tail at its 3'- end, i.e., the poly-A tail is not masked or followed at its 3'-end by a nucleotide other than A. In some embodiments, a poly-A tail may comprise at least 20, at least 30, at least 40, at least 80, or at least 100 and up to 500, up to 400, up to 300, up to 200, or up to 150 nucleotides. In some embodiments, the poly-A tail may essentially consist of at least 20, at least 30, at least 40, at least 80, or at least 100 and up to 500, up to 400, up to 300, up to 200, or up to 150 nucleotides. In some embodiments, the poly-A tail may consist of at least 20, at least 30, at least 40, at least 80, or at least 100 and up to 500, up to 400, up to 300, up to 200, or up to 150 nucleotides. In some embodiments, the poly-A tail comprises the poly-A tail shown in SEQ ID NO: 8. In some embodiments, the poly-A tail comprises at least 100 nucleotides. In some embodiments, the poly-A tail comprises about 150 nucleotides. In some embodiments, the poly-A tail comprises about 120 nucleotides.

[0192] In some embodiments, RNA (in particular, mRNA) described in present disclosure comprises a 5'-UTR and / or a 3'-UTR. The term "untranslated region" or "UTR" relates to a region in a DNA molecule which is transcribed but is not translated into an amino acid sequence, or to the corresponding region in an RNA molecule, such as an mRNA molecule. An untranslated region (UTR) can be present 5' (upstream) of an open reading frame (5'-UTR) and / or 3' (downstream) of an open reading frame (3'-UTR). A 5'-UTR, if present, is located at the 5'-end, upstream of the start codon of a protein-encoding region. A 5'-UTR is downstream of the 5'-cap (if present), e.g., directly adjacent to the 5'-cap. A 3'-UTR, if present, is located at the 3'-end, downstream of the termination codon of a protein-encoding region, but the term "3'-UTR" does generally not include the poly-A sequence. Thus, the 3'-UTR is upstream of the poly-A sequence (if present), e.g., directly adjacent to the poly-A sequence. Incorporation of a 3'-UTR into the 3'-non translated region of an RNA (preferably mRNA) molecule can result in an enhancement in translation efficiency. A synergistic effect may be achieved by incorporating two or more of such 3'-UTRs (which are preferably arranged in a head-to-tail orientation; cf., e.g., Holtkamp et al., Blood 108, 4009-4017 (2006)). The 3'-UTRs may be autologous or heterologous to the RNA (e.g., mRNA) into which they are introduced. In certain embodiments, the 3'-UTR is derived from a globin gene or mRNA, such as a gene or mRNA of alpha2-globin, alpha1-globin, or beta-globin, e.g., beta-globin, e.g., human beta-globin. For example, the RNA (e.g., mRNA) may be modified by the replacement of the existing 3'-UTR with or the insertion of one or more, e.g., two copies of a 3'-UTR derived from a globin gene, such as alpha2-globin, alpha1-globin, beta-globin, e.g., beta-globin, e.g., human beta-globin.

[0193] A particularly preferred 5'-UTR comprises the nucleotide sequence of SEQ ID NO: 6. A particularly preferred 3'-UTR comprises the nucleotide sequence of SEQ ID NO: 7.

[0194] In some embodiments, RNA comprises a 5'-UTR comprising the nucleotide sequence of SEQ ID NO: 6, or a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 6.

[0195] In some embodiments, RNA comprises a 3'-UTR comprising the nucleotide sequence of SEQ ID NO: 7, or a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 7.

[0196] The RNA (in particular, mRNA) described herein may have modified ribonucleotides in order to increase its stability and / or decrease immunogenicity and / or decrease cytotoxicity. For example, in some embodiments, uridine in the RNA (in particular, mRNA) described herein is replaced (partially or completely, preferably completely) by a modified nucleoside. In some embodiments, the modified nucleoside is a modified uridine.

[0197] In some embodiments, the modified uridine replacing uridine is selected from the group consisting of pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), 5-methyl-uridine (m5U), and combinations thereof.

[0198] In some embodiments, the modified nucleoside replacing (partially or completely, preferably completely) uridine in the mRNA may be any one or more of 3-methyl-uridine (m3U), 5-methoxy-uridine (mo5U), 5-aza-uridine, 6-aza-uridine, 2-thio-5-aza-uridine, 2-thio-uridine (s2U), 4-thio-uridine (s4U), 4-thio-pseudouridine, 2-thio-pseudouridine, 5-hydroxy-uridine (ho5U), 5-aminoallyl-uridine, 5-halo-uridine (e.g., 5-iodo-uridineor 5-bromo-uridine), uridine 5-oxyacetic acid (cmo5U), uridine 5-oxyacetic acid methyl ester (mcmo5U), 5-carboxymethyl-uridine (cm5U), 1-carboxymethyl-pseudouridine, 5-carboxyhydroxymethyl-uridine (chm5U), 5-carboxyhydroxymethyl-uridine methyl ester (mchm5U), 5-methoxycarbonylmethyl-uridine (mcm5U), 5-methoxycarbonylmethyl-2-thio-uridine (mcm5s2U), 5-aminomethyl-2-thio-uridine (nm5s2U), 5-methylaminomethyl-uridine (mnm5U), 1-ethyl-pseudouridine, 5-methylaminomethyl-2-thio-uridine (mnm5s2U), 5-methylaminomethyl-2-seleno-uridine (mnm5se2U), 5-carbamoylmethyl-uridine (ncm5U), 5-carboxymethylaminomethyl-uridine (cmnm5U), 5-carboxymethylaminomethyl-2-thio-uridine (cmnm5s2U), 5-propynyl-uridine, 1-propynyl-pseudouridine, 5-taurinomethyl-uridine (τm5U), 1-taurinomethyl-pseudouridine, 5-taurinomethyl-2-thio-uridine(τm5s2U), 1-taurinomethyl-4-thio-pseudouridine), 5-methyl-2-thio-uridine (m5s2U), 1-methyl-4-thio-pseudouridine (m1s4ψ), 4-thio-1-methyl-pseudouridine, 3-methyl-pseudouridine (m3ψ), 2-thio-1-methyl-pseudouridine, 1-methyl-1-deaza-pseudouridine, 2-thio-1-methyl-1-deaza-pseudouridine, dihydrouridine (D), dihydropseudouridine, 5,6-dihydrouridine, 5-methyl-dihydrouridine (m5D), 2-thio-dihydrouridine, 2-thio-dihydropseudouridine, 2-methoxy-uridine, 2-methoxy-4-thio-uridine, 4-methoxy-pseudouridine, 4-methoxy-2-thio-pseudouridine, N1-methyl-pseudouridine, 3-(3-amino-3-carboxypropyl)uridine (acp3U), 1-methyl-3-(3-amino-3-carboxypropyl)pseudouridine (acp3 ψ), 5-(isopentenylaminomethyl)uridine (inm5U), 5-(isopentenylaminomethyl)-2-thio-uridine (inm5s2U), α-thio-uridine, 2'-O-methyl-uridine (Um), 5,2'-O-dimethyl-uridine (m5Um), 2'-O-methyl-pseudouridine (ψm), 2-thio-2'-O-methyl-uridine (s2Um), 5-methoxycarbonylmethyl-2'-O-methyl-uridine (mcm5Um), 5-carbamoylmethyl-2'-O-methyl-uridine (ncm5Um), 5-carboxymethylaminomethyl-2'-O-methyl-uridine (cmnm5Um), 3,2'-O-dimethyl-uridine (m3Um), 5-(isopentenylaminomethyl)-2'-O-methyl-uridine (inm5Um), 1-thio-uridine, deoxythymidine, 2'-F-ara-uridine, 2'-F-uridine, 2'-OH-ara-uridine, 5-(2-carbomethoxyvinyl) uridine, 5-[3-(1-E-propenylamino)uridine, or any other modified uridine known in the art.

[0199] An RNA (preferably mRNA) which is modified by pseudouridine (replacing partially or completely, preferably completely, uridine) is referred to herein as "Ψ-modified", whereas the term "m1Ψ-modified" means that the RNA (preferably mRNA) contains N(1)-methylpseudouridine (replacing partially or completely, preferably completely, uridine). Furthermore, the term "m5U-modified" means that the RNA (preferably mRNA) contains 5-methyluridine (replacing partially or completely, preferably completely, uridine). Such Ψ- or m1Ψ- or m5U-modified RNAs usually exhibit decreased immunogenicity compared to their unmodified forms and, thus, are preferred in applications where the induction of an immune response is to be avoided or minimized. In some embodiments, the RNA (preferably mRNA) contains N(1)-methylpseudouridine replacing completely uridine.

[0200] The codons of the RNA (in particular, mRNA) described in the present disclosure may further be optimized, e.g., to increase the GC content of the RNA and / or to replace codons which are rare in the cell (or subject) in which the peptide or polypeptide of interest is to be expressed by codons which are synonymous frequent codons in said cell (or subject). In some embodiments, the amino acid sequence encoded by the RNA (in particular, mRNA) described in the present disclosure is encoded by a coding sequence which is codon-optimized and / or the G / C content of which is increased compared to wild type coding sequence. This also includes embodiments, wherein one or more sequence regions of the coding sequence are codon-optimized and / or increased in the G / C content compared to the corresponding sequence regions of the wild type coding sequence. In some embodiments, the codon-optimization and / or the increase in the G / C content preferably does not change the sequence of the encoded amino acid sequence.

[0201] The term "codon-optimized" refers to the alteration of codons in the coding region of a nucleic acid molecule to reflect the typical codon usage of a host organism without preferably altering the amino acid sequence encoded by the nucleic acid molecule. Within the context of the present disclosure, coding regions may be codon-optimized for optimal expression in a subject to be treated using the RNA (in particular, mRNA) described herein. Codon-optimization is based on the finding that the translation efficiency is also determined by a different frequency in the occurrence of tRNAs in cells. Thus, the sequence of RNA (in particular, mRNA) may be modified such that codons for which frequently occurring tRNAs are available are inserted in place of "rare codons".

[0202] In some embodiments, the guanosine / cytosine (G / C) content of the coding region of the RNA (in particular, mRNA) described herein is increased compared to the G / C content of the corresponding coding sequence of the wild type RNA, wherein the amino acid sequence encoded by the RNA is preferably not modified compared to the amino acid sequence encoded by the wild type RNA. This modification of the RNA sequence is based on the fact that the sequence of any RNA region to be translated is important for efficient translation of that RNA. Sequences having an increased G (guanosine) / C (cytosine) content are more stable than sequences having an increased A (adenosine) / U (uracil) content. In respect to the fact that several codons code for one and the same amino acid (so-called degeneration of the genetic code), the most favorable codons for the stability can be determined (so-called alternative codon usage). Depending on the amino acid to be encoded by the RNA, there are various possibilities for modification of the RNA sequence, compared to its wild type sequence. In particular, codons which contain A and / or U nucleotides can be modified by substituting these codons by other codons, which code for the same amino acids but contain no A and / or U or contain a lower content of A and / or U nucleotides.

[0203] In various embodiments, the G / C content of the coding region of the RNA (in particular, mRNA) described herein is increased by at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 55%, or even more compared to the G / C content of the coding region of the wild type RNA.

[0204] A combination of the above described modifications, i.e., incorporation of a 5'-cap structure, incorporation of a poly-A sequence, unmasking of a poly-A sequence, alteration of the 5'-and / or 3'-UTR (such as incorporation of one or more 3'-UTRs), replacing one or more naturally occurring nucleotides with synthetic nucleotides (e.g., 5-methylcytidine for cytidine and / or pseudouridine (Ψ) or N(1)-methylpseudouridine (m1Ψ) or 5-methyluridine (m5U) for uridine), and codon optimization, has a synergistic influence on the stability of RNA (preferably mRNA) and increase in translation efficiency. Thus, in some embodiments, the RNA (in particular, mRNA) described in the present disclosure contains a combination of at least two, at least three, at least four or all five of the above-mentioned modifications, i.e., (i) incorporation of a 5'-cap structure, (ii) incorporation of a poly-A sequence, unmasking of a poly-A sequence; (iii) alteration of the 5'- and / or 3'-UTR (such as incorporation of one or more 3'-UTRs); (iv) replacing one or more naturally occurring nucleotides with synthetic nucleotides (e.g., 5-methylcytidine for cytidine and / or pseudouridine (Ψ) or N(1)-methylpseudouridine (m1Ψ) or 5-methyluridine (m5U) for uridine), and (v) codon optimization.

[0205] Some aspects of the disclosure involve the targeted delivery of the mRNA disclosed herein to certain cells or tissues. In some embodiments, the disclosure involves targeting the lymphatic system, in particular secondary lymphoid organs, more specifically spleen. Targeting the lymphatic system, in particular secondary lymphoid organs, more specifically spleen is in particular preferred if the RNA (in particular, mRNA) administered is RNA (in particular, mRNA) encoding an antigen or epitope for inducing an immune response. In some embodiments, the target cell is a spleen cell. In some embodiments, the target cell is an antigen presenting cell such as a professional antigen presenting cell in the spleen. In some embodiments, the target cell is a dendritic cell in the spleen. The "lymphatic system" is part of the circulatory system and an important part of the immune system, comprising a network of lymphatic vessels that carry lymph. The lymphatic system consists of lymphatic organs, a conducting network of lymphatic vessels, and the circulating lymph. The primary or central lymphoid organs generate lymphocytes from immature progenitor cells. The thymus and the bone marrow constitute the primary lymphoid organs. Secondary or peripheral lymphoid organs, which include lymph nodes and the spleen, maintain mature naive lymphocytes and initiate an adaptive immune response.

[0206] Lipid-based mRNA delivery systems have an inherent preference to the liver, where, depending on the composition of the mRNA delivery sytems used, mRNA expression in the liver can be obtained. Liver accumulation is caused by the discontinuous nature of the hepatic vasculature or the lipid metabolism (liposomes and lipid or cholesterol conjugates). In some embodiments, the target organ for mRNA expression is liver and the target tissue is liver tissue. The delivery to such target tissue is preferred, in particular, if presence of mRNA or of the encoded peptide or polypeptide in this organ or tissue is desired and / or if it is desired to express large amounts of the encoded peptide or polypeptide and / or if systemic presence of the encoded peptide or polypeptide, in particular in significant amounts, is desired or required.

[0207] In some embodiments, after administration of the RNA (in particular, mRNA) compositions / formulations described herein, at least a portion of the RNA is delivered to a target cell or target organ. In some embodiments, at least a portion of the RNA is delivered to the cytosol of the target cell. In some embodiments, the RNA is RNA (in particular, mRNA) encoding a peptide or polypeptide and the RNA is translated by the target cell to produce the peptide or polypeptide. In some embodiments, the target cell is a cell in the liver. In some embodiments, the target cell is a muscle cell. In some embodiments, the target cell is an endothelial cell. In some embodiments the target cell is a tumor cell or a cell in the tumor microenvironment. In some embodiments, the target cell is a blood cell. In some embodiments, the target cell is a cell in the lymph nodes. In some embodiments, the target cell is a cell in the lung. In some embodiments, the target cell is a cell in the skin. In some embodiments, the target cell is a spleen cell. In some embodiments, the target cell is an antigen presenting cell such as a professional antigen presenting cell in the spleen. In some embodiments, the target cell is a dendritic cell in the spleen. In some embodiments, the target cell is a T cell. In some embodiments, the target cell is a B cell. In some embodiments, the target cell is a NK cell. In some embodiments, the target cell is a monocyte. Thus, RNA (in particular, mRNA) compositions / formulations described herein may be used for delivering RNA to such target cell.Pharmaceutically active peptides or polypeptides

[0208] "Encoding" refers to the inherent property of specific sequences of nucleotides in a polynucleotide, such as a gene, a cDNA, or an RNA (in particular, mRNA), to serve as templates for synthesis of other polymers and macromolecules in biological processes having either a defined sequence of nucleotides (i.e., rRNA, tRNA and mRNA) or a defined sequence of amino acids and the biological properties resulting therefrom. Thus, a gene encodes a protein if transcription and translation of mRNA corresponding to that gene produces the protein in a cell or other biological system. Both the coding strand, the nucleotide sequence of which is identical to the mRNA sequence and is usually provided in sequence listings, and the noncoding strand, used as the template for transcription of a gene or cDNA, can be referred to as encoding the protein or other product of that gene or cDNA.

[0209] In some embodiments, RNA (in particular, mRNA) described in the present disclosure comprises a nucleic acid sequence encoding a peptide or polypeptide, e.g., a pharmaceutically active peptide or polypeptide.

[0210] In some embodiments, RNA (in particular, mRNA) described in the present disclosure comprises a nucleic acid sequence encoding a peptide or polypeptide, preferably a pharmaceutically active peptide or polypeptide, and is capable of expressing said peptide or polypeptide, in particular if transferred into a cell or subject. Thus, in some embodiments, the RNA (in particular, mRNA) described in the present disclosure contains a coding region (open reading frame (ORF)) encoding a peptide or polypeptide, e.g., encoding a pharmaceutically active peptide or polypeptide. In this respect, an "open reading frame" or "ORF" is a continuous stretch of codons beginning with a start codon and ending with a stop codon. Such nucleic acid encoding a pharmaceutically active peptide or polypeptide is also referred to herein as "pharmaceutically active nucleic acid". In particular, such RNA encoding a pharmaceutically active peptide or polypeptide is also referred to herein as "pharmaceutically active RNA" and such mRNA encoding a pharmaceutically active peptide or polypeptide is also referred to herein as "pharmaceutically active mRNA". In some embodiments, RNA used in the present disclosure comprises a nucleic acid sequence encoding more than one peptide or polypeptide, e.g., two, three, four or more peptides or polypeptides.

[0211] According to the present disclosure, the term "pharmaceutically active peptide or polypeptide" means a peptide or polypeptide that can be used in the treatment of an individual where the expression of the peptide or polypeptide would be of benefit, e.g., in ameliorating the symptoms of a disease. Preferably, a pharmaceutically active peptide or polypeptide has curative or palliative properties and may be administered to ameliorate, relieve, alleviate, reverse, delay onset of or lessen the severity of one or more symptoms of a disease. In some embodiments, a pharmaceutically active peptide or polypeptide has a positive or advantageous effect on the condition or disease state of an individual when administered to the individual in a therapeutically effective amount. A pharmaceutically active peptide or polypeptide may have prophylactic properties and may be used to delay the onset of a disease or to lessen the severity of such disease. The term "pharmaceutically active peptide or polypeptide" includes entire peptides or polypeptides, and can also refer to pharmaceutically active fragments thereof. It can also include pharmaceutically active variants and / or analogs of a peptide or polypeptide.

[0212] Specific examples of pharmaceutically active peptides and polypeptides include, but are not limited to, immunostimulants, e.g., cytokines, hormones, adhesion molecules, immunoglobulins, immunologically active compounds, growth factors, protease inhibitors, enzymes, receptors, apoptosis regulators, transcription factors, tumor suppressor proteins, structural proteins, reprogramming factors, genomic engineering proteins, and blood proteins. In some embodiments, the pharmaceutically active peptide and polypeptide includes a replacement protein.

[0213] An "immunostimulant" is any substance that stimulates the immune system by inducing activation or increasing activity of any of the immune system's components, in particular immune effector cells. The immunostimulant may be pro-inflammatory (e.g., when treating infections or cancer), or anti-inflammatory (e.g., when treating autoimmune diseases). According to one aspect, the immunostimulant is a cytokine or a variant thereof. Examples of cytokines include interferons, such as interferon-alpha (IFN-α) or interferon-gamma (IFN-y), interleukins, such as IL2, IL7, IL12, IL15 and IL23, colony stimulating factors, such as M-CSF and GM-CSF, and tumor necrosis factor. According to another aspect, the immunostimulant includes an adjuvant-type immunostimulatory agent such as APC Toll-like Receptor agonists or costimulatory / cell adhesion membrane proteins. Examples of Toll-like Receptor agonists include costimulatory / adhesion proteins such as CD80, CD86, and ICAM-1.

[0214] The term "cytokines" relates to proteins which have a molecular weight of about 5 to 60 kDa and which participate in cell signaling (e.g., paracrine, endocrine, and / or autocrine signaling). In particular, when released, cytokines exert an effect on the behavior of cells around the place of their release. Examples of cytokines include lymphokines, interleukins, chemokines, interferons, and tumor necrosis factors (TNFs). According to the present disclosure, cytokines do not include hormones or growth factors. Cytokines differ from hormones in that (i) they usually act at much more variable concentrations than hormones and (ii) generally are made by a broad range of cells (nearly all nucleated cells can produce cytokines). Interferons are usually characterized by antiviral, antiproliferative and immunomodulatory activities. Interferons are proteins that alter and regulate the transcription of genes within a cell by binding to interferon receptors on the regulated cell's surface, thereby preventing viral replication within the cells. The interferons can be grouped into two types. Particular examples of cytokines include erythropoietin (EPO), colony stimulating factor (CSF), granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), tumor necrosis factor (TNF), bone morphogenetic protein (BMP), interferon alfa (IFNα), interferon beta (IFNβ), interferon gamma (INFy), interleukin 2 (IL-2), interleukin 4 (IL-4), interleukin 10 (IL-10), interleukin 11 (IL-11), interleukin 12 (IL-12), interleukin 15 (IL-15), and interleukin 21 (IL-21), as well as variants and derivatives thereof.

[0215] According to the disclosure, a cytokine may be a naturally occurring cytokine or a functional fragment or variant thereof. A cytokine may be human cytokine and may be derived from any vertebrate, especially any mammal. One particularly preferred cytokine is interferon-a. Immunostimulants may be provided to a subject by administering to the subject RNA encoding an immunostimulant in a formulation for preferential delivery of RNA to liver or liver tissue. The delivery of RNA to such target organ or tissue is preferred, in particular, if it is desired to express large amounts of the immunostimulant and / or if systemic presence of the immunostimulant, in particular in significant amounts, is desired or required.

[0216] RNA delivery systems have an inherent preference to the liver. This pertains to lipid-based particles, cationic and neutral nanoparticles, in particular lipid nanoparticles.

[0217] Examples of suitable immunostimulants for targeting liver are cytokines involved in T cell proliferation and / or maintenance. Examples of suitable cytokines include IL2 or IL7, fragments and variants thereof, and fusion proteins of these cytokines, fragments and variants, such as extended-PK cytokines.

[0218] In another embodiment, RNA encoding an immunostimulant may be administered in a formulation for preferential delivery of RNA to the lymphatic system, in particular secondary lymphoid organs, more specifically spleen. The delivery of an immunostimulant to such target tissue is preferred, in particular, if presence of the immunostimulant in this organ or tissue is desired (e.g., for inducing an immune response, in particular in case immunostimulants such as cytokines are required during T-cell priming or for activation of resident immune cells), while it is not desired that the immunostimulant is present systemically, in particular in significant amounts (e.g., because the immunostimulant has systemic toxicity).

[0219] Examples of suitable immunostimulants are cytokines involved in T cell priming. Examples of suitable cytokines include IL12, IL15, IFN-α, or IFN-β, fragments and variants thereof, and fusion proteins of these cytokines, fragments and variants, such as extended-PK cytokines. Interferons (IFNs) are a group of signaling proteins made and released by host cells in response to the presence of several pathogens, such as viruses, bacteria, parasites, and also tumor cells.

[0220] In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses.

[0221] Based on the type of receptor through which they signal, interferons are typically divided among three classes: type I interferon, type II interferon, and type III interferon.

[0222] All type I interferons bind to a specific cell surface receptor complex known as the IFN-α / β receptor (IFNAR) that consists of IFNAR1 and IFNAR2 chains.

[0223] The type I interferons present in humans are IFNα, IFNβ, IFNε, IFNκ and IFNω. In general, type I interferons are produced when the body recognizes a virus that has invaded it. They are produced by fibroblasts and monocytes. Once released, type I interferons bind to specific receptors on target cells, which leads to expression of proteins that will prevent the virus from producing and replicating its RNA and DNA.

[0224] The IFNα proteins are produced mainly by plasmacytoid dendritic cells (pDCs). They are mainly involved in innate immunity against viral infection. The genes responsible for their synthesis come in 13 subtypes that are called IFNA1, IFNA2, IFNA4, IFNA5, IFNA6, IFNA7, IFNA8, IFNA10, IFNA13, IFNA14, IFNA16, IFNA17, IFNA21. These genes are found together in a cluster on chromosome 9.

[0225] The IFNβ proteins are produced in large quantities by fibroblasts. They have antiviral activity that is involved mainly in innate immune response. Two types of IFNβ have been described, IFNβ1 and IFNβ3. The natural and recombinant forms of IFNβ1 have antiviral, antibacterial, and anticancer properties.

[0226] Type II interferon (IFNy in humans) is also known as immune interferon and is activated by IL12. Furthermore, type II interferons are released by cytotoxic T cells and T helper cells.

[0227] Type III interferons signal through a receptor complex consisting of IL10R2 (also called CRF2-4) and IFNLR1 (also called CRF2-12). Although discovered more recently than type I and type II IFNs, recent information demonstrates the importance of type III IFNs in some types of virus or fungal infections.

[0228] In general, type I and II interferons are responsible for regulating and activating the immune response.

[0229] According to the disclosure, a type I interferon is preferably IFNα or IFNβ, more preferably IFNα.

[0230] According to the disclosure, an interferon may be a naturally occurring interferon or a functional fragment or variant thereof. An interferon may be human interferon and may be derived from any vertebrate, especially any mammal.

[0231] Interleukins (ILs) are a group of cytokines (secreted proteins and signal molecules) that can be divided into four major groups based on distinguishing structural features. However, their amino acid sequence similarity is rather weak (typically 15-25% identity). The human genome encodes more than 50 interleukins and related proteins.

[0232] According to the disclosure, an interleukin may be a naturally occurring interleukin or a functional fragment or variant thereof. An interleukin may be human interleukin and may be derived from any vertebrate, especially any mammal.

[0233] Immunostimulant polypeptides described herein can be prepared as fusion or chimeric polypeptides that include an immunostimulant portion and a heterologous polypeptide (i.e., a polypeptide that is not an immunostimulant). The immunostimulant may be fused to an extended-PK group, which increases circulation half-life. Non-limiting examples of extended-PK groups are described infra. It should be understood that other PK groups that increase the circulation half-life of immunostimulants such as cytokines, or variants thereof, are also applicable to the present disclosure. In certain embodiments, the extended-PK group is a serum albumin domain (e.g., mouse serum albumin, human serum albumin).

[0234] As used herein, the term "PK" is an acronym for "pharmacokinetic" and encompasses properties of a compound including, by way of example, absorption, distribution, metabolism, and elimination by a subject. As used herein, an "extended-PK group" refers to a protein, peptide, or moiety that increases the circulation half-life of a biologically active molecule when fused to or administered together with the biologically active molecule. Examples of an extended-PK group include serum albumin (e.g., HSA), Immunoglobulin Fc or Fc fragments and variants thereof, transferrin and variants thereof, and human serum albumin (HSA) binders (as disclosed in U.S. Publication Nos. 2005 / 0287153 and 2007 / 0003549). Other exemplary extended-PK groups are disclosed in Kontermann, Expert Opin Biol Ther, 2016 Jul;16(7):903-15.

[0235] As used herein, an "extended-PK" immunostimulant refers to an immunostimulant moiety in combination with an extended-PK group. In some embodiments, the extended-PK immunostimulant is a fusion protein in which an immunostimulant moiety is linked or fused to an extended-PK group.

[0236] In certain embodiments, the serum half-life of an extended-PK immunostimulant is increased relative to the immunostimulant alone (i.e., the immunostimulant not fused to an extended-PK group). In certain embodiments, the serum half-life of the extended-PK immunostimulant is at least 20%, at least 40%, at least 60%, at least 80%, at least 100%, at least 120%, at least 150%, at least 180%, at least 200%, at least 400%, at least 600%, at least 800%, or at least 1000% longer relative to the serum half-life of the immunostimulant alone. In certain embodiments, the serum half-life of the extended-PK immunostimulant is at least 1.5-fold, 2-fold, 2.5-fold, 3-fold, 3.5-fold, 4-fold, 4.5-fold, 5-fold, 6-fold, 7-fold, 8-fold, 10-fold, 12-fold, 13-fold, 15-fold, 17-fold, 20-fold, 22-fold, 25-fold, 27-fold, 30-fold, 35-fold, 40-fold, or 50-fold greater than the serum half-life of the immunostimulant alone. In certain embodiments, the serum half-life of the extended-PK immunostimulant is at least 10 hours, 15 hours, 20 hours, 25 hours, 30 hours, 35 hours, 40 hours, 50 hours, 60 hours, 70 hours, 80 hours, 90 hours, 100 hours, 110 hours, 120 hours, 130 hours, 135 hours, 140 hours, 150 hours, 160 hours, or 200 hours.

[0237] As used herein, "half-life" refers to the time taken for the serum or plasma concentration of a compound such as a peptide or polypeptide to reduce by 50%, in vivo, for example due to degradation and / or clearance or sequestration by natural mechanisms. An extended-PK immunostimulant suitable for use herein is stabilized in vivo and its half-life increased by, e.g., fusion to serum albumin (e.g., HSA or MSA), which resist degradation and / or clearance or sequestration. The half-life can be determined in any manner known per se, such as by pharmacokinetic analysis. Suitable techniques will be clear to the person skilled in the art, and may for example generally involve the steps of suitably administering a suitable dose of the amino acid sequence or compound to a subject; collecting blood samples or other samples from said subject at regular intervals; determining the level or concentration of the amino acid sequence or compound in said blood sample; and calculating, from (a plot of) the data thus obtained, the time until the level or concentration of the amino acid sequence or compound has been reduced by 50% compared to the initial level upon dosing. Further details are provided in, e.g., standard handbooks, such as Kenneth, A. et al., Chemical Stability of Pharmaceuticals: A Handbook for Pharmacists and in Peters et al., Pharmacokinetic Analysis: A Practical Approach (1996). Reference is also made to Gibaldi, M. et al., Pharmacokinetics, 2nd Rev. Edition, Marcel Dekker (1982).

[0238] In certain embodiments, the extended-PK group includes serum albumin, or fragments thereof or variants of the serum albumin or fragments thereof (all of which for the purpose of the present disclosure are comprised by the term "albumin"). Polypeptides described herein may be fused to albumin (or a fragment or variant thereof) to form albumin fusion proteins. Such albumin fusion proteins are described in U.S. Publication No. 20070048282.

[0239] As used herein, "albumin fusion protein" refers to a protein formed by the fusion of at least one molecule of albumin (or a fragment or variant thereof) to at least one molecule of a protein such as a therapeutic protein, in particular an immunostimulant. The albumin fusion protein may be generated by translation of a nucleic acid in which a polynucleotide encoding a therapeutic protein is joined in-frame with a polynucleotide encoding an albumin. The therapeutic protein and albumin, once part of the albumin fusion protein, may each be referred to as a "portion", "region" or "moiety" of the albumin fusion protein (e.g., a "therapeutic protein portion" or an "albumin protein portion"). In a highly preferred embodiment, an albumin fusion protein comprises at least one molecule of a therapeutic protein (including, but not limited to a mature form of the therapeutic protein) and at least one molecule of albumin (including but not limited to a mature form of albumin). In some embodiments, an albumin fusion protein is processed by a host cell such as a cell of the target organ for administered RNA, e.g. a liver cell, and secreted into the circulation. Processing of the nascent albumin fusion protein that occurs in the secretory pathways of the host cell used for expression of the RNA may include, but is not limited to signal peptide cleavage; formation of disulfide bonds; proper folding; addition and processing of carbohydrates (such as for example, N- and O-linked glycosylation); specific proteolytic cleavages; and / or assembly into multimeric proteins. An albumin fusion protein is preferably encoded by RNA in a non-processed form which in particular has a signal peptide at its N-terminus and following secretion by a cell is preferably present in the processed form wherein in particular the signal peptide has been cleaved off. In a most preferred embodiment, the "processed form of an albumin fusion protein" refers to an albumin fusion protein product which has undergone N-terminal signal peptide cleavage, herein also referred to as a "mature albumin fusion protein". In preferred embodiments, albumin fusion proteins comprising a therapeutic protein have a higher plasma stability compared to the plasma stability of the same therapeutic protein when not fused to albumin. Plasma stability typically refers to the time period between when the therapeutic protein is administered in vivo and carried into the bloodstream and when the therapeutic protein is degraded and cleared from the bloodstream, into an organ, such as the kidney or liver, that ultimately clears the therapeutic protein from the body. Plasma stability is calculated in terms of the half-life of the therapeutic protein in the bloodstream. The half-life of the therapeutic protein in the bloodstream can be readily determined by common assays known in the art.

[0240] As used herein, "albumin" refers collectively to albumin protein or amino acid sequence, or an albumin fragment or variant, having one or more functional activities (e.g., biological activities) of albumin. In particular, "albumin" refers to human albumin or fragments or variants thereof especially the mature form of human albumin, or albumin from other vertebrates or fragments thereof, or variants of these molecules. The albumin may be derived from any vertebrate, especially any mammal, for example human, cow, sheep, or pig. Non-mammalian albumins include, but are not limited to, hen and salmon. The albumin portion of the albumin fusion protein may be from a different animal than the therapeutic protein portion.

[0241] In certain embodiments, the albumin is human serum albumin (HSA), or fragments or variants thereof, such as those disclosed in US 5,876,969, WO 2011 / 124718, WO 2013 / 075066, and WO 2011 / 0514789.

[0242] The terms, human serum albumin (HSA) and human albumin (HA) are used interchangeably herein. The terms, "albumin and "serum albumin" are broader, and encompass human serum albumin (and fragments and variants thereof) as well as albumin from other species (and fragments and variants thereof).

[0243] As used herein, a fragment of albumin sufficient to prolong the therapeutic activity or plasma stability of the therapeutic protein refers to a fragment of albumin sufficient in length or structure to stabilize or prolong the therapeutic activity or plasma stability of the protein so that the plasma stability of the therapeutic protein portion of the albumin fusion protein is prolonged or extended compared to the plasma stability in the non-fusion state.

[0244] The albumin portion of the albumin fusion proteins may comprise the full length of the albumin sequence, or may include one or more fragments thereof that are capable of stabilizing or prolonging the therapeutic activity or plasma stability. Such fragments may be of 10 or more amino acids in length or may include about 15, 20, 25, 30, 50, or more contiguous amino acids from the albumin sequence or may include part or all of specific domains of albumin. For instance, one or more fragments of HSA spanning the first two immunoglobulin-like domains may be used. In a preferred embodiment, the HSA fragment is the mature form of HSA.

[0245] Generally speaking, an albumin fragment or variant will be at least 100 amino acids long, preferably at least 150 amino acids long.

[0246] According to the disclosure, albumin may be naturally occurring albumin or a fragment or variant thereof. Albumin may be human albumin and may be derived from any vertebrate, especially any mammal.

[0247] Preferably, the albumin fusion protein comprises albumin as the N-terminal portion, and a therapeutic protein as the C-terminal portion. Alternatively, an albumin fusion protein comprising albumin as the C-terminal portion, and a therapeutic protein as the N-terminal portion may also be used. In other embodiments, the albumin fusion protein has a therapeutic protein fused to both the N-terminus and the C-terminus of albumin. In a preferred embodiment, the therapeutic proteins fused at the N- and C-termini are the same therapeutic proteins. In another preferred embodiment, the therapeutic proteins fused at the N- and C-termini are different therapeutic proteins. In some embodiments, the different therapeutic proteins are both cytokines.

[0248] In some embodiments, the therapeutic protein(s) is (are) joined to the albumin through (a) peptide linker(s). A peptide linker between the fused portions may provide greater physical separation between the moieties and thus maximize the accessibility of the therapeutic protein portion, for instance, for binding to its cognate receptor. The peptide linker may consist of amino acids such that it is flexible or more rigid. The linker sequence may be cleavable by a protease or chemically.

[0249] As used herein, the term "Fc region" refers to the portion of a native immunoglobulin formed by the respective Fc domains (or Fc moieties) of its two heavy chains. As used herein, the term "Fc domain" refers to a portion or fragment of a single immunoglobulin (Ig) heavy chain wherein the Fc domain does not comprise an Fv domain. In certain embodiments, an Fc domain begins in the hinge region just upstream of the papain cleavage site and ends at the C-terminus of the antibody. Accordingly, a complete Fc domain comprises at least a hinge domain, a CH2 domain, and a CH3 domain. In certain embodiments, an Fc domain comprises at least one of: a hinge (e.g., upper, middle, and / or lower hinge region) domain, a CH2 domain, a CH3 domain, a CH4 domain, or a variant, portion, or fragment thereof. In certain embodiments, an Fc domain comprises a complete Fc domain (i.e., a hinge domain, a CH2 domain, and a CH3 domain). In certain embodiments, an Fc domain comprises a hinge domain (or portion thereof) fused to a CH3 domain (or portion thereof). In certain embodiments, an Fc domain comprises a CH2 domain (or portion thereof) fused to a CH3 domain (or portion thereof). In certain embodiments, an Fc domain consists of a CH3 domain or portion thereof. In certain embodiments, an Fc domain consists of a hinge domain (or portion thereof) and a CH3 domain (or portion thereof). In certain embodiments, an Fc domain consists of a CH2 domain (or portion thereof) and a CH3 domain. In certain embodiments, an Fc domain consists of a hinge domain (or portion thereof) and a CH2 domain (or portion thereof). In certain embodiments, an Fc domain lacks at least a portion of a CH2 domain (e.g., all or part of a CH2 domain). An Fc domain herein generally refers to a polypeptide comprising all or part of the Fc domain of an immunoglobulin heavy-chain. This includes, but is not limited to, polypeptides comprising the entire CH1, hinge, CH2, and / or CH3 domains as well as fragments of such peptides comprising only, e.g., the hinge, CH2, and CH3 domain. The Fc domain may be derived from an immunoglobulin of any species and / or any subtype, including, but not limited to, a human IgG1, IgG2, IgG3, IgG4, IgD, IgA, IgE, or IgM antibody. The Fc domain encompasses native Fc and Fc variant molecules. As set forth herein, it will be understood by one of ordinary skill in the art that any Fc domain may be modified such that it varies in amino acid sequence from the native Fc domain of a naturally occurring immunoglobulin molecule. In certain embodiments, the Fc domain has reduced effector function (e.g., FcyR binding).

[0250] The Fc domains of a polypeptide described herein may be derived from different immunoglobulin molecules. For example, an Fc domain of a polypeptide may comprise a CH2 and / or CH3 domain derived from an IgG1 molecule and a hinge region derived from an IgG3 molecule. In another example, an Fc domain can comprise a chimeric hinge region derived, in part, from an IgG1 molecule and, in part, from an IgG3 molecule. In another example, an Fc domain can comprise a chimeric hinge derived, in part, from an IgG1 molecule and, in part, from an IgG4 molecule.

[0251] In certain embodiments, an extended-PK group includes an Fc domain or fragments thereof or variants of the Fc domain or fragments thereof (all of which for the purpose of the present disclosure are comprised by the term "Fc domain"). The Fc domain does not contain a variable region that binds to antigen. Fc domains suitable for use in the present disclosure may be obtained from a number of different sources. In certain embodiments, an Fc domain is derived from a human immunoglobulin. In certain embodiments, the Fc domain is from a human IgG1 constant region. It is understood, however, that the Fc domain may be derived from an immunoglobulin of another mammalian species, including for example, a rodent (e.g. a mouse, rat, rabbit, guinea pig) or non-human primate (e.g. chimpanzee, macaque) species. Moreover, the Fc domain (or a fragment or variant thereof) may be derived from any immunoglobulin class, including IgM, IgG, IgD, IgA, and IgE, and any immunoglobulin isotype, including IgG1, IgG2, IgG3, and IgG4.

[0252] A variety of Fc domain gene sequences (e.g., mouse and human constant region gene sequences) are available in the form of publicly accessible deposits. Constant region domains comprising an Fc domain sequence can be selected lacking a particular effector function and / or with a particular modification to reduce immunogenicity. Many sequences of antibodies and antibody-encoding genes have been published and suitable Fc domain sequences (e.g. hinge, CH2, and / or CH3 sequences, or fragments or variants thereof) can be derived from these sequences using art recognized techniques.

[0253] In certain embodiments, the extended-PK group is a serum albumin binding protein such as those described in US2005 / 0287153, US2007 / 0003549, US2007 / 0178082, US2007 / 0269422, US2010 / 0113339, WO2009 / 083804, and WO2009 / 133208.

[0254] In certain embodiments, the extended-PK group is transferrin, as disclosed in US 7,176,278 and US 8,158,579.

[0255] In certain embodiments, the extended-PK group is a serum immunoglobulin binding protein such as those disclosed in US2007 / 0178082, US2014 / 0220017, and US2017 / 0145062.

[0256] In certain embodiments, the extended-PK group is a fibronectin (Fn)-based scaffold domain protein that binds to serum albumin, such as those disclosed in US2012 / 0094909.

[0257] Methods of making fibronectin-based scaffold domain proteins are also disclosed in US2012 / 0094909. A non-limiting example of a Fn3-based extended-PK group is Fn3(HSA), i.e., a Fn3 protein that binds to human serum albumin.

[0258] In certain aspects, the extended-PK immunostimulant, suitable for use according to the disclosure, can employ one or more peptide linkers. As used herein, the term "peptide linker" refers to a peptide or polypeptide sequence which connects two or more domains (e.g., the extended-PK moiety and an immunostimulant moiety) in a linear amino acid sequence of a polypeptide chain. For example, peptide linkers may be used to connect an immunostimulant moiety to a HSA domain.

[0259] Linkers suitable for fusing the extended-PK group to, e.g., an immunostimulant are well known in the art. Exemplary linkers include glycine-serine-polypeptide linkers, glycine-proline-polypeptide linkers, and proline-alanine polypeptide linkers. In certain embodiments, the linker is a glycine-serine-polypeptide linker, i.e., a peptide that consists of glycine and serine residues.

[0260] In some embodiments, a pharmaceutically active peptide or polypeptide comprises a replacement protein. In these embodiments, the present disclosure provides a method for treatment of a subject having a disorder requiring protein replacement (e.g., protein deficiency disorders) comprising administering to the subject RNA (in particular, mRNA) as described herein encoding a replacement protein. The term "protein replacement" refers to the introduction of a protein (including functional variants thereof) into a subject having a deficiency in such protein. The term also refers to the introduction of a protein into a subject otherwise requiring or benefiting from providing a protein, e.g., suffering from protein insufficiency. The term "disorder characterized by a protein deficiency" refers to any disorder that presents with a pathology caused by absent or insufficient amounts of a protein. This term encompasses protein folding disorders, i.e., conformational disorders, that result in a biologically inactive protein product. Protein insufficiency can be involved in infectious diseases, immunosuppression, organ failure, glandular problems, radiation illness, nutritional deficiency, poisoning, or other environmental or external insults.

[0261] The term "hormones" relates to a class of signaling molecules produced by glands, wherein signaling usually includes the following steps: (i) synthesis of a hormone in a particular tissue; (ii) storage and secretion; (iii) transport of the hormone to its target; (iv) binding of the hormone by a receptor; (v) relay and amplification of the signal; and (vi) breakdown of the hormone. Hormones differ from cytokines in that (1) hormones usually act in less variable concentrations and (2) generally are made by specific kinds of cells. In some embodiments, a "hormone" is a peptide or polypeptide hormone, such as insulin, vasopressin, prolactin, adrenocorticotropic hormone (ACTH), thyroid hormone, growth hormones (such as human grown hormone or bovine somatotropin), oxytocin, atrial-natriuretic peptide (ANP), glucagon, somatostatin, cholecystokinin, gastrin, and leptins.

[0262] The term "adhesion molecules" relates to proteins which are located on the surface of a cell and which are involved in binding of the cell with other cells or with the extracellular matrix (ECM). Adhesion molecules are typically transmembrane receptors and can be classified as calcium-independent (e.g., integrins, immunoglobulin superfamily, lymphocyte homing receptors) and calcium-dependent (cadherins and selectins). Particular examples of adhesion molecules are integrins, lymphocyte homing receptors, selectins (e.g., P-selectin), and addressins.

[0263] Integrins are also involved in signal transduction. In particular, upon ligand binding, integrins modulate cell signaling pathways, e.g., pathways of transmembrane protein kinases such as receptor tyrosine kinases (RTK). Such regulation can lead to cellular growth, division, survival, or differentiation or to apoptosis. Particular examples of integrins include: α 1 β 1 , α 2 β 1 , α 3 β 1 , α 4 β 1 , α 5 β 1 , α 6 β 1 , α 7 β 1 , α L β 2 , α M β 2 , α IIb β 3 , α V β 1 , α V β 3 , α V β 5 , α V β 6 , α V β 8 , and α 6 β 4 .

[0264] The term "immunoglobulins" or "immunoglobulin superfamily" refers to molecules which are involved in the recognition, binding, and / or adhesion processes of cells. Molecules belonging to this superfamily share the feature that they contain a region known as immunoglobulin domain or fold. Members of the immunoglobulin superfamily include antibodies (e.g., IgG), T cell receptors (TCRs), major histocompatibility complex (MHC) molecules, co-receptors (e.g., CD4, CD8, CD19), antigen receptor accessory molecules (e.g., CD-3y, CD3-6, CD-3ε, CD79a, CD79b), co-stimulatory or inhibitory molecules (e.g., CD28, CD80, CD86), and other.

[0265] The term "immunologically active compound" relates to any compound altering an immune response, e.g., by inducing and / or suppressing maturation of immune cells, inducing and / or suppressing cytokine biosynthesis, and / or altering humoral immunity by stimulating antibody production by B cells. Immunologically active compounds possess potent immunostimulating activity including, but not limited to, antiviral and antitumor activity, and can also down-regulate other aspects of the immune response, for example shifting the immune response away from a TH2 immune response, which is useful for treating a wide range of TH2 mediated diseases. Immunologically active compounds can be useful as vaccine adjuvants. Particular examples of immunologically active compounds include interleukins, colony stimulating factor (CSF), granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), erythropoietin, tumor necrosis factor (TNF), interferons, integrins, addressins, selectins, homing receptors, and antigens, in particular tumor-associated antigens, pathogen-associated antigens (such as bacterial, parasitic, or viral antigens), allergens, and autoantigens. An immunologically active compound may be a vaccine antigen, i.e., an antigen whose inoculation into a subject induces an immune response.

[0266] In some embodiments, RNA (in particular, mRNA) described in the present disclosure comprises a nucleic acid sequence encoding a peptide or polypeptide comprising an epitope for inducing an immune response against an antigen in a subject. The "peptide or polypeptide comprising an epitope for inducing an immune response against an antigen in a subject" is also designated herein as "vaccine antigen", "peptide and protein antigen" or simply "antigen".

[0267] In some embodiments, the RNA (in particular, mRNA) encoding vaccine antigen is a single-stranded, 5' capped mRNA that is translated into the respective protein upon entering cells of a subject being administered the RNA, e.g., antigen-presenting cells (APCs). Preferably, the RNA (i) contains structural elements optimized for maximal efficacy of the RNA with respect to stability and translational efficiency (5' cap, 5' UTR, 3' UTR, poly(A) sequence); (ii) is modified for optimized efficacy of the RNA (e.g., increased translation efficacy, decreased immunogenicity, and / or decreased cytotoxicity) (e.g., by replacing (partially or completely, preferably completely) naturally occurring nucleosides (in particular cytidine) with synthetic nucleosides (e.g., modified nucleosides selected from the group consisting of pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine); and / or codon-optimization), or (iii) both (i) and (ii).

[0268] In some embodiments, beta-S-ARCA(D1) is utilized as specific capping structure at the 5'-end of the RNA. In some embodiments, the 5'-UTR comprises the nucleotide sequence of SEQ ID NO: 6, or a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 6. In some embodiments, the 3'-UTR comprises the nucleotide sequence of SEQ ID NO: 7, or a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 7. In some embodiments, the poly(A) sequence is 110 nucleotides in length and consists of a stretch of 30 adenosine residues, followed by a 10 nucleotide linker sequence and another 70 adenosine residues. This poly(A) sequence was designed to enhance RNA stability and translational efficiency in dendritic cells. In some embodiments, the poly(A) sequence comprises the nucleotide sequence of SEQ ID NO: 8, or a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 8. In some embodiments, the RNA comprises a modified nucleoside in place of uridine. In some embodiments, the modified nucleoside replacing (partially or completely, preferably completely) uridine is selected from the group consisting of pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine. In some embodiments, the RNA encoding the vaccine antigen has a coding sequence (a) which is codon-optimized, (b) the G / C content of which is increased compared to the wild type coding sequence, or (c) both (a) and (b).

[0269] In some embodiments, the RNA encoding the vaccine antigen is expressed in cells of the subject to provide the vaccine antigen. In some embodiments, expression of the vaccine antigen is at the cell surface. In some embodiments, the vaccine antigen is presented in the context of MHC. In some embodiments, the RNA encoding the vaccine antigen is transiently expressed in cells of the subject. In some embodiments, the RNA encoding the vaccine antigen is administered systemically. In some embodiments, after systemic administration of the RNA encoding the vaccine antigen, expression of the RNA encoding the vaccine antigen in spleen occurs. In some embodiments, after systemic administration of the RNA encoding the vaccine antigen, expression of the RNA encoding the vaccine antigen in antigen presenting cells, preferably professional antigen presenting cells occurs. In some embodiments, the antigen presenting cells are selected from the group consisting of dendritic cells, macrophages and B cells. In some embodiments, after systemic administration of the RNA encoding the vaccine antigen, no or essentially no expression of the RNA encoding the vaccine antigen in lung and / or liver occurs. In some embodiments, after systemic administration of the RNA encoding the vaccine antigen, expression of the RNA encoding the vaccine antigen in spleen is at least 5-fold the amount of expression in lung.

[0270] The vaccine antigen comprises an epitope for inducing an immune response against an antigen in a subject. Accordingly, the vaccine antigen comprises an antigenic sequence for inducing an immune response against an antigen in a subject. Such antigenic sequence may correspond to a target antigen or disease-associated antigen, e.g., a protein of an infectious agent (e.g., viral or bacterial antigen) or tumor antigen, or may correspond to an immunogenic variant thereof, or an immunogenic fragment of the target antigen or disease-associated antigen or the immunogenic variant thereof. Thus, the antigenic sequence may comprise at least an epitope of a target antigen or disease-associated antigen or an immunogenic variant thereof. The antigenic sequences, e.g., epitopes, suitable for use according to the disclosure typically may be derived from a target antigen, i.e. the antigen against which an immune response is to be elicited. For example, the antigenic sequences contained within the vaccine antigen may be a target antigen or a fragment or variant of a target antigen.

[0271] The antigenic sequence or a procession product thereof, e.g., a fragment thereof, may bind to the antigen receptor such as TCR or CAR carried by immune effector cells. In some embodiments, the antigenic sequence is selected from the group consisting of the antigen expressed by a target cell to which the immune effector cells are targeted or a fragment thereof, or a variant of the antigenic sequence or the fragment.

[0272] A vaccine antigen which may be provided to a subject according to the present disclosure by administering RNA encoding the vaccine antigen, preferably results in the induction of an immune response, e.g., in the stimulation, priming and / or expansion of immune effector cells, in the subject being provided the vaccine antigen. Said immune response, e.g., stimulated, primed and / or expanded immune effector cells, is preferably directed against a target antigen, in particular a target antigen expressed by diseased cells, tissues and / or organs, i.e., a disease-associated antigen. Thus, a vaccine antigen may comprise the disease-associated antigen, or a fragment or variant thereof. In some embodiments, such fragment or variant is immunologically equivalent to the disease-associated antigen.

[0273] In the context of the present disclosure, the term "fragment of an antigen" or "variant of an antigen" means an agent which results in the induction of an immune response, e.g., in the stimulation, priming and / or expansion of immune effector cells, which immune response, e.g., stimulated, primed and / or expanded immune effector cells, targets the antigen, i.e. a disease-associated antigen, in particular when presented by diseased cells, tissues and / or organs. Thus, the vaccine antigen may correspond to or may comprise the disease-associated antigen, may correspond to or may comprise a fragment of the disease-associated antigen or may correspond to or may comprise an antigen which is homologous to the disease-associated antigen or a fragment thereof. If the vaccine antigen comprises a fragment of the disease-associated antigen or an amino acid sequence which is homologous to a fragment of the disease-associated antigen said fragment or amino acid sequence may comprise an epitope of the disease-associated antigen to which the antigen receptor of the immune effector cells is targeted or a sequence which is homologous to an epitope of the disease-associated antigen. Thus, according to the disclosure, a vaccine antigen may comprise an immunogenic fragment of a disease-associated antigen or an amino acid sequence being homologous to an immunogenic fragment of a disease-associated antigen. An "immunogenic fragment of an antigen" according to the disclosure preferably relates to a fragment of an antigen which is capable of inducing an immune response against, e.g., stimulating, priming and / or expanding immune effector cells carrying an antigen receptor binding to, the antigen or cells expressing the antigen. It is preferred that the vaccine antigen (similar to the disease-associated antigen) provides the relevant epitope for binding by the antigen receptor present on the immune effector cells. In some embodiments, the vaccine antigen or a fragment thereof (similar to the disease-associated antigen) is expressed on the surface of a cell such as an antigen-presenting cell (optionally in the context of MHC) so as to provide the relevant epitope for binding by immune effector cells. The vaccine antigen may be a recombinant antigen.

[0274] In some embodiments of all aspects of the invention, the RNA encoding the vaccine antigen is expressed in cells of a subject to provide the antigen or a procession product thereof for binding by the antigen receptor expressed by immune effector cells, said binding resulting in stimulation, priming and / or expansion of the immune effector cells. An "antigen" according to the present disclosure covers any substance that will elicit an immune response and / or any substance against which an immune response or an immune mechanism such as a cellular response and / or humoral response is directed. This also includes situations wherein the antigen is processed into antigen peptides and an immune response or an immune mechanism is directed against one or more antigen peptides, in particular if presented in the context of MHC molecules. In particular, an "antigen" relates to any substance, such as a peptide or polypeptide, that reacts specifically with antibodies or T-lymphocytes (T-cells). The term "antigen" may comprise a molecule that comprises at least one epitope, such as a T cell epitope. In some embodiments, an antigen is a molecule which, optionally after processing, induces an immune reaction, which may be specific for the antigen (including cells expressing the antigen). In some embodiments, an antigen is a disease-associated antigen, such as a tumor antigen, a viral antigen, or a bacterial antigen, or an epitope derived from such antigen. In some embodiments, an antigen is presented or present on the surface of cells of the immune system such as antigen presenting cells like dendritic cells or macrophages. An antigen or a procession product thereof such as a T cell epitope is in some embodiments bound by an antigen receptor. Accordingly, an antigen or a procession product thereof may react specifically with immune effector cells such as T-lymphocytes (T cells).

[0275] The term "autoantigen" or "self-antigen" refers to an antigen which originates from within the body of a subject (i.e., the autoantigen can also be called "autologous antigen") and which produces an abnormally vigorous immune response against this normal part of the body. Such vigorous immune reactions against autoantigens may be the cause of "autoimmune diseases".

[0276] According to the present disclosure, any suitable antigen may be used, which is a candidate for an immune response, wherein the immune response may comprise a humoral or cellular immune response, or both. In the context of some embodiments of the present disclosure, the antigen is presented by a cell, such as by an antigen presenting cell, in the context of MHC molecules, which results in an immune response against the antigen. An antigen may be a product which corresponds to or is derived from a naturally occurring antigen. Such naturally occurring antigens may include or may be derived from allergens, viruses, bacteria, fungi, parasites and other infectious agents and pathogens or an antigen may also be a tumor antigen. According to the present disclosure, an antigen may correspond to a naturally occurring product, for example, a viral protein, or a part thereof.

[0277] The term "disease-associated antigen" is used in its broadest sense to refer to any antigen associated with a disease. A disease-associated antigen is a molecule which contains epitopes that will stimulate a host's immune system to make a cellular antigen-specific immune response and / or a humoral antibody response against the disease. Disease-associated antigens include pathogen-associated antigens, i.e., antigens which are associated with infection by microbes, typically microbial antigens (such as bacterial or viral antigens), or antigens associated with cancer, typically tumors, such as tumor antigens.

[0278] In some embodiments, the antigen is a tumor antigen, i.e., a part of a tumor cell, in particular those which primarily occur intracellularly or as surface antigens of tumor cells. In another embodiment, the antigen is a pathogen-associated antigen, i.e., an antigen derived from a pathogen, e.g., from a virus, bacterium, unicellular organism, or parasite, for example a viral antigen such as viral ribonucleoprotein or coat protein. In some embodiments, the antigen should be presented by MHC molecules which results in modulation, in particular activation of cells of the immune system, such as CD4+ and CD8+ lymphocytes, in particular via the modulation of the activity of a T-cell receptor.

[0279] The term "tumor antigen" or "tumor-associated antigen" refers to a constituent of cancer cells which may be derived from the cytoplasm, the cell surface or the cell nucleus. In particular, it refers to those antigens which are produced intracellularly or as surface antigens on tumor cells. For example, tumor antigens include the carcinoembryonal antigen, α1-fetoprotein, isoferritin, and fetal sulphoglycoprotein, α2-H-ferroprotein and γ-fetoprotein, as well as various virus tumor antigens. According to some embodiments of the present disclosure, a tumor antigen comprises any antigen which is characteristic for tumors or cancers as well as for tumor or cancer cells with respect to type and / or expression level.

[0280] The term "viral antigen" refers to any viral component having antigenic properties, i.e., being able to provoke an immune response in an individual. The viral antigen may be a viral ribonucleoprotein or an envelope protein.

[0281] The term "bacterial antigen" refers to any bacterial component having antigenic properties, i.e. being able to provoke an immune response in an individual. The bacterial antigen may be derived from the cell wall or cytoplasm membrane of the bacterium.

[0282] The term "epitope" refers to an antigenic determinant in a molecule such as an antigen, i.e., to a part in or fragment of the molecule that is recognized by the immune system, for example, that is recognized by antibodies, T cells or B cells, in particular when presented in the context of MHC molecules. An epitope of a protein may comprises a continuous or discontinuous portion of said protein and, e.g., may be between about 5 and about 100, between about 5 and about 50, between about 8 and about 30, or about 10 and about 25 amino acids in length, for example, the epitope may be preferably 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 amino acids in length. In some embodiments, the epitope in the context of the present disclosure is a T cell epitope.

[0283] Terms such as "epitope", "fragment of an antigen", "immunogenic peptide" and "antigen peptide" are used interchangeably herein and, e.g., may relate to an incomplete representation of an antigen which is, e.g., capable of eliciting an immune response against the antigen or a cell expressing or comprising and presenting the antigen. In some embodiments, the terms relate to an immunogenic portion of an antigen. In some embodiments, it is a portion of an antigen that is recognized (i.e., specifically bound) by a T cell receptor, in particular if presented in the context of MHC molecules. Certain preferred immunogenic portions bind to an MHC class I or class II molecule. The term "epitope" refers to a part or fragment of a molecule such as an antigen that is recognized by the immune system. For example, the epitope may be recognized by T cells, B cells or antibodies. An epitope of an antigen may include a continuous or discontinuous portion of the antigen and may be between about 5 and about 100, such as between about 5 and about 50, between about 8 and about 30, or between about 8 and about 25 amino acids in length, for example, the epitope may be 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 amino acids in length. In some embodiments, an epitope is between about 10 and about 25 amino acids in length. The term "epitope" includes T cell epitopes.

[0284] The term "T cell epitope" refers to a part or fragment of a protein that is recognized by a T cell when presented in the context of MHC molecules. The term "major histocompatibility complex" and the abbreviation "MHC" includes MHC class I and MHC class II molecules and relates to a complex of genes which is present in all vertebrates. MHC proteins or molecules are important for signaling between lymphocytes and antigen presenting cells or diseased cells in immune reactions, wherein the MHC proteins or molecules bind peptide epitopes and present them for recognition by T cell receptors on T cells. The proteins encoded by the MHC are expressed on the surface of cells, and display both self-antigens (peptide fragments from the cell itself) and non-self-antigens (e.g., fragments of invading microorganisms) to a T cell. In the case of class I MHC / peptide complexes, the binding peptides are typically about 8 to about 10 amino acids long although longer or shorter peptides may be effective. In the case of class II MHC / peptide complexes, the binding peptides are typically about 10 to about 25 amino acids long and are in particular about 13 to about 18 amino acids long, whereas longer and shorter peptides may be effective.

[0285] The peptide and polypeptide antigen can be 2 to 100 amino acids, including for example, 5 amino acids, 10 amino acids, 15 amino acids, 20 amino acids, 25 amino acids, 30 amino acids, 35 amino acids, 40 amino acids, 45 amino acids, or 50 amino acids in length. In some embodiments, a peptide can be greater than 50 amino acids. In some embodiments, the peptide can be greater than 100 amino acids.

[0286] The peptide or polypeptide antigen can be any peptide or polypeptide that can induce or increase the ability of the immune system to develop antibodies and T cell responses to the peptide or polypeptide.

[0287] In some embodiments, vaccine antigen, i.e., an antigen whose inoculation into a subject induces an immune response, is recognized by an immune effector cell. In some embodiments, the vaccine antigen if recognized by an immune effector cell is able to induce in the presence of appropriate co-stimulatory signals, stimulation, priming and / or expansion of the immune effector cell carrying an antigen receptor recognizing the vaccine antigen. In the context of the embodiments of the present disclosure, the vaccine antigen may be, e.g., presented or present on the surface of a cell, such as an antigen presenting cell.

[0288] In some embodiments, an antigen is expressed in a diseased cell (such as tumor cell or an infected cell).

[0289] In some embodiments, an antigen is presented by a diseased cell (such as tumor cell or an infected cell). In some embodiments, an antigen receptor is a TCR which binds to an epitope of an antigen presented in the context of MHC. In some embodiments, binding of a TCR when expressed by T cells and / or present on T cells to an antigen presented by cells such as antigen presenting cells results in stimulation, priming and / or expansion of said T cells. In some embodiments, binding of a TCR when expressed by T cells and / or present on T cells to an antigen presented on diseased cells results in cytolysis and / or apoptosis of the diseased cells, wherein said T cells release cytotoxic factors, e.g., perforins and granzymes.

[0290] In some embodiments, an antigen is expressed on the surface of a diseased cell (such as tumor cell or an infected cell). In some embodiments, an antigen receptor is a CAR which binds to an extracellular domain or to an epitope in an extracellular domain of an antigen. In some embodiments, a CAR binds to native epitopes of an antigen present on the surface of living cells. In some embodiments, binding of a CAR when expressed by T cells and / or present on T cells to an antigen present on cells such as antigen presenting cells results in stimulation, priming and / or expansion of said T cells. In some embodiments, binding of a CAR when expressed by T cells and / or present on T cells to an antigen present on diseased cells results in cytolysis and / or apoptosis of the diseased cells, wherein said T cells preferably release cytotoxic factors, e.g., perforins and granzymes.

[0291] According to some embodiments, an amino acid sequence enhancing antigen processing and / or presentation is fused, either directly or through a linker, to an antigenic peptide or polypeptide (antigenic sequence). Accordingly, in some embodiments, the RNA described herein comprises at least one coding region encoding an antigenic peptide or polypeptide and an amino acid sequence enhancing antigen processing and / or presentation.

[0292] In some embodiments, antigen for vaccination which may be administered in the form of RNA coding therefor comprises a naturally occurring antigen or a fragment such as an epitope thereof.

[0293] Such amino acid sequences enhancing antigen processing and / or presentation are preferably located at the C-terminus of the antigenic peptide or polypeptide (and optionally at the C-terminus of an amino acid sequence which breaks immunological tolerance), without being limited thereto. Amino acid sequences enhancing antigen processing and / or presentation as defined herein preferably improve antigen processing and presentation. In some embodiments, the amino acid sequence enhancing antigen processing and / or presentation as defined herein includes, without being limited thereto, sequences derived from the human MHC class I complex (HLA-B51, haplotype A2, B27 / B51, Cw2 / Cw3), in particular a sequence comprising the amino acid sequence of SEQ ID NO: 2 or a functional variant thereof.

[0294] In some embodiments, an amino acid sequence enhancing antigen processing and / or presentation comprises the amino acid sequence of SEQ ID NO: 2, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 2, or a functional fragment of the amino acid sequence of SEQ ID NO: 2, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 2. In some embodiments, an amino acid sequence enhancing antigen processing and / or presentation comprises the amino acid sequence of SEQ ID NO: 2.

[0295] Accordingly, in some embodiments, the RNA described herein comprises at least one coding region encoding an antigenic peptide or polypeptide and an amino acid sequence enhancing antigen processing and / or presentation, said amino acid sequence enhancing antigen processing and / or presentation preferably being fused to the antigenic peptide or polypeptide, more preferably to the C-terminus of the antigenic peptide or polypeptide as described herein.

[0296] Furthermore, a secretory sequence, e.g., a sequence comprising the amino acid sequence of SEQ ID NO: 1, may be fused to the N-terminus of the antigenic peptide or polypeptide. Amino acid sequences derived from tetanus toxoid of Clostridium tetani may be employed to overcome self-tolerance mechanisms in order to efficiently mount an immune response to self-antigens by providing T-cell help during priming.

[0297] It is known that tetanus toxoid heavy chain includes epitopes that can bind promiscuously to MHC class II alleles and induce CD4 +< memory T cells in almost all tetanus vaccinated individuals. In addition, the combination of tetanus toxoid (TT) helper epitopes with tumor-associated antigens is known to improve the immune stimulation compared to application of tumor-associated antigen alone by providing CD4 +< -mediated T-cell help during priming. To reduce the risk of stimulating CD8 +< T cells with the tetanus sequences which might compete with the intended induction of tumor antigen-specific T-cell response, not the whole fragment C of tetanus toxoid is used as it is known to contain CD8 +< T-cell epitopes. Two peptide sequences containing promiscuously binding helper epitopes were selected alternatively to ensure binding to as many MHC class II alleles as possible. Based on the data of the ex vivo studies the well-known epitopes p2 (QYIKANSKFIGITEL; TT 830-844 ; SEQ ID NO: 9) and p16 (MTNSVDDALINSTKIYSYFPSVISKVNQGAQG; TT 578-609 ; SEQ ID NO: 10) were selected. The p2 epitope was already used for peptide vaccination in clinical trials to boost anti-melanoma activity.

[0298] Non-clinical data showed that RNA vaccines encoding both a tumor antigen plus promiscuously binding tetanus toxoid sequences lead to enhanced CD8 +< T-cell responses directed against the tumor antigen and improved break of tolerance. Immunomonitoring data from patients vaccinated with vaccines including those sequences fused in frame with the tumor antigen-specific sequences reveal that the tetanus sequences chosen are able to induce tetanus-specific T-cell responses in almost all patients.

[0299] According to some embodiments, an amino acid sequence which breaks immunological tolerance is fused, either directly or through a linker, e.g., a linker having the amino acid sequence according to SEQ ID NO: 4, to the antigenic peptide or polypeptide.

[0300] Such amino acid sequences which break immunological tolerance are preferably located at the C-terminus of the antigenic peptide or polypeptide (and optionally at the N-terminus of the amino acid sequence enhancing antigen processing and / or presentation, wherein the amino acid sequence which breaks immunological tolerance and the amino acid sequence enhancing antigen processing and / or presentation may be fused either directly or through a linker, e.g., a linker having the amino acid sequence according to SEQ ID NO: 5), without being limited thereto. Amino acid sequences which break immunological tolerance as defined herein preferably improve T cell responses. In some embodiments, the amino acid sequence which breaks immunological tolerance as defined herein includes, without being limited thereto, sequences derived from tetanus toxoid-derived helper sequences p2 and p16 (P2P16), in particular a sequence comprising the amino acid sequence of SEQ ID NO: 3 or a functional variant thereof.

[0301] In some embodiments, an amino acid sequence which breaks immunological tolerance comprises the amino acid sequence of SEQ ID NO: 3, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 3, or a functional fragment of the amino acid sequence of SEQ ID NO: 3, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 3. In some embodiments, an amino acid sequence which breaks immunological tolerance comprises the amino acid sequence of SEQ ID NO: 3.

[0302] In the following, embodiments of vaccine RNAs are described, wherein certain terms used when describing elements thereof have the following meanings: cap: 5'-cap structure selected from the group consisting of m 2 7,2'O< G(5')ppSp(5')G (in particular its D1 diastereomer), m 2 7,3'O< G(5')ppp(5')G, and m 2 7,3'-O< Gppp(m 1 2'-O< )ApG. hAg-Kozak: 5'-UTR sequence of the human alpha-globin mRNA with an optimized 'Kozak sequence' to increase translational efficiency. sec / MITD: Fusion-protein tags derived from the sequence encoding the human MHC class I complex (HLA-B51, haplotype A2, B27 / B51, Cw2 / Cw3), which have been shown to improve antigen processing and presentation. Sec corresponds to the 78 bp fragment coding for the secretory signal peptide, which guides translocation of the nascent polypeptide chain into the endoplasmatic reticulum. MITD corresponds to the transmembrane and cytoplasmic domain of the MHC class I molecule, also called MHC class I trafficking domain. Antigen: Sequences encoding the respective vaccine antigen / epitope. Glycine-serine linker (GS): Sequences coding for short peptide linkers predominantly consisting of the amino acids glycine (G) and serine (S), as commonly used for fusion proteins. P2P16: Sequence coding for tetanus toxoid-derived helper epitopes to break immunological tolerance. FI element: The 3'-UTR is a combination of two sequence elements derived from the "amino terminal enhancer of split" (AES) mRNA (called F) and the mitochondrial encoded 12S ribosomal RNA (called I). These were identified by an ex vivo selection process for sequences that confer RNA stability and augment total protein expression. A30L70: A poly(A)-tail measuring 110 nucleotides in length, consisting of a stretch of 30 adenosine residues, followed by a 10 nucleotide linker sequence and another 70 adenosine residues designed to enhance RNA stability and translational efficiency in dendritic cells.

[0303] In some embodiments, vaccine RNA described herein has one of the following structures: cap-hAg-Kozak-sec-GS(1)-Antigen-GS(2)-P2P16-GS(3)-MITD-FI-A30L70 beta-S-ARCA(D1)-hAg-Kozak-sec-GS(1)-Antigen-GS(2)-P2P16-GS(3)-MITD-FI-A30L70

[0304] In some embodiments, vaccine antigen described herein has the structure: sec-GS(1)-Antigen-GS(2)-P2P16-GS(3)-MITD

[0305] In some embodiments, hAg-Kozak comprises the nucleotide sequence of SEQ ID NO: 6. In some embodiments, sec comprises the amino acid sequence of SEQ ID NO: 1. In some embodiments, P2P16 comprises the amino acid sequence of SEQ ID NO: 3. In some embodiments, MITD comprises the amino acid sequence of SEQ ID NO: 2. In some embodiments, GS(1) comprises the amino acid sequence of SEQ ID NO: 4. In some embodiments, GS(2) comprises the amino acid sequence of SEQ ID NO: 4. In some embodiments, GS(3) comprises the amino acid sequence of SEQ ID NO: 5. In some embodiments, FI comprises the nucleotide sequence of SEQ ID NO: 7. In some embodiments, A30L70 comprises the nucleotide sequence of SEQ ID NO: 8.

[0306] In some embodiments, the sequence encoding the vaccine antigen / epitope comprises a modified nucleoside replacing (partially or completely, preferably completely) uridine, wherein the modified nucleoside is selected from the group consisting of pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine.

[0307] In some embodiments, the sequence encoding the vaccine antigen / epitope is codon-optimized.

[0308] In some embodiments, the G / C content of the sequence encoding the vaccine antigen / epitope is increased compared to the wild type coding sequence.

[0309] In some embodiments, an antigen receptor is an antibody or B cell receptor which binds to an epitope in an antigen. In some embodiments, an antibody or B cell receptor binds to native epitopes of an antigen.

[0310] The term "expressed on the cell surface" or "associated with the cell surface" means that a molecule such as an antigen is associated with and located at the plasma membrane of a cell, wherein at least a part of the molecule faces the extracellular space of said cell and is accessible from the outside of said cell, e.g., by antibodies located outside the cell. In this context, a part may be, e.g., at least 4, at least 8, at least 12, or at least 20 amino acids. The association may be direct or indirect. For example, the association may be by one or more transmembrane domains, one or more lipid anchors, or by the interaction with any other protein, lipid, saccharide, or other structure that can be found on the outer leaflet of the plasma membrane of a cell. For example, a molecule associated with the surface of a cell may be a transmembrane protein having an extracellular portion or may be a protein associated with the surface of a cell by interacting with another protein that is a transmembrane protein.

[0311] "Cell surface" or "surface of a cell" is used in accordance with its normal meaning in the art, and thus includes the outside of the cell which is accessible to binding by proteins and other molecules. An antigen is expressed on the surface of cells if it is located at the surface of said cells and is accessible to binding by, e.g., antigen-specific antibodies added to the cells. In some embodiments, an antigen expressed on the surface of cells is an integral membrane protein having an extracellular portion which may be recognized by a CAR.

[0312] The term "extracellular portion" or "exodomain" in the context of the present disclosure refers to a part of a molecule such as a protein that is facing the extracellular space of a cell and preferably is accessible from the outside of said cell, e.g., by binding molecules such as antibodies located outside the cell. In some embodiments, the term refers to one or more extracellular loops or domains or a fragment thereof.

[0313] The terms "T cell" and "T lymphocyte" are used interchangeably herein and include T helper cells (CD4+ T cells) and cytotoxic T cells (CTLs, CD8 +< T cells) which comprise cytolytic T cells. The term "antigen-specific T cell" or similar terms relate to a T cell which recognizes the antigen to which the T cell is targeted, in particular when presented on the surface of antigen presenting cells or diseased cells such as cancer cells in the context of MHC molecules and preferably exerts effector functions of T cells. T cells are considered to be specific for antigen if the cells kill target cells expressing an antigen. T cell specificity may be evaluated using any of a variety of standard techniques, for example, within a chromium release assay or proliferation assay. Alternatively, synthesis of lymphokines (such as interferon-γ) can be measured.

[0314] The term "target" shall mean an agent such as a cell or tissue which is a target for an immune response such as a cellular immune response. Targets include cells that present an antigen or an antigen epitope, i.e., a peptide fragment derived from an antigen. In some embodiments, the target cell is a cell expressing an antigen and presenting said antigen with class I MHC.

[0315] "Antigen processing" refers to the degradation of an antigen into processing products which are fragments of said antigen (e.g., the degradation of a polypeptide into peptides) and the association of one or more of these fragments (e.g., via binding) with MHC molecules for presentation by cells, such as antigen-presenting cells to specific T-cells. Antigen-presenting cells can be distinguished in professional antigen presenting cells and non-professional antigen presenting cells.

[0316] The term "professional antigen presenting cells" relates to antigen presenting cells which constitutively express the Major Histocompatibility Complex class II (MHC class II) molecules required for interaction with naive T cells. If a T cell interacts with the MHC class II molecule complex on the membrane of the antigen presenting cell, the antigen presenting cell produces a co-stimulatory molecule inducing activation of the T cell. Professional antigen presenting cells comprise dendritic cells and macrophages.

[0317] The term "non-professional antigen presenting cells" relates to antigen presenting cells which do not constitutively express MHC class II molecules, but upon stimulation by certain cytokines such as interferon-gamma. Exemplary, non-professional antigen presenting cells include fibroblasts, thymic epithelial cells, thyroid epithelial cells, glial cells, pancreatic beta cells or vascular endothelial cells.

[0318] The term "dendritic cell" (DC) refers to a subtype of phagocytic cells belonging to the class of antigen presenting cells. In some embodiments, dendritic cells are derived from hematopoietic bone marrow progenitor cells. These progenitor cells initially transform into immature dendritic cells. These immature cells are characterized by high phagocytic activity and low T cell activation potential. Immature dendritic cells constantly sample the surrounding environment for pathogens such as viruses and bacteria. Once they have come into contact with a presentable antigen, they become activated into mature dendritic cells and begin to migrate to the spleen or to the lymph node. Immature dendritic cells phagocytose pathogens and degrade their proteins into small pieces and upon maturation present those fragments at their cell surface using MHC molecules. Simultaneously, they upregulate cell-surface receptors that act as co-receptors in T cell activation such as CD80, CD86, and CD40 greatly enhancing their ability to activate T cells. They also upregulate CCR7, a chemotactic receptor that induces the dendritic cell to travel through the blood stream to the spleen or through the lymphatic system to a lymph node. Here they act as antigen-presenting cells and activate helper T cells and killer T cells as well as B cells by presenting them antigens, alongside non-antigen specific co-stimulatory signals. Thus, dendritic cells can actively induce a T cell- or B cell-related immune response. In some embodiments, the dendritic cells are splenic dendritic cells.

[0319] The term "macrophage" refers to a subgroup of phagocytic cells produced by the differentiation of monocytes. Macrophages which are activated by inflammation, immune cytokines or microbial products nonspecifically engulf and kill foreign pathogens within the macrophage by hydrolytic and oxidative attack resulting in degradation of the pathogen.

[0320] Peptides from degraded proteins are displayed on the macrophage cell surface where they can be recognized by T cells, and they can directly interact with antibodies on the B cell surface, resulting in T and B cell activation and further stimulation of the immune response. Macrophages belong to the class of antigen presenting cells. In some embodiments, the macrophages are splenic macrophages.

[0321] By "antigen-responsive CTL" is meant a CD8 +< T-cell that is responsive to an antigen or a peptide derived from said antigen, which is presented with class I MHC on the surface of antigen presenting cells.

[0322] According to the disclosure, CTL responsiveness may include sustained calcium flux, cell division, production of cytokines such as IFN-γ and TNF-α, up-regulation of activation markers such as CD44 and CD69, and specific cytolytic killing of tumor antigen expressing target cells. CTL responsiveness may also be determined using an artificial reporter that accurately indicates CTL responsiveness.

[0323] "Activation" or "stimulation", as used herein, refers to the state of a cell that has been sufficiently stimulated to induce detectable cellular proliferation, such as an immune effector cell such as T cell. Activation can also be associated with initiation of signaling pathways, induced cytokine production, and detectable effector functions. The term "activated immune effector cells" refers to, among other things, immune effector cells that are undergoing cell division.

[0324] The term "priming" refers to a process wherein an immune effector cell such as a T cell has its first contact with its specific antigen and causes differentiation into effector cells such as effector T cells.

[0325] The term "expansion" refers to a process wherein a specific entity is multiplied. In some embodiments, the term is used in the context of an immunological response in which immune effector cells are stimulated by an antigen, proliferate, and the specific immune effector cell recognizing said antigen is amplified. In some embodiments, expansion leads to differentiation of the immune effector cells.

[0326] The terms "immune response" and "immune reaction" are used herein interchangeably in their conventional meaning and refer to an integrated bodily response to an antigen and may refer to a cellular immune response, a humoral immune response, or both. According to the disclosure, the term "immune response to" or "immune response against" with respect to an agent such as an antigen, cell or tissue, relates to an immune response such as a cellular response directed against the agent. An immune response may comprise one or more reactions selected from the group consisting of developing antibodies against one or more antigens and expansion of antigen-specific T-lymphocytes, such as CD4 +< and CD8 +< T-lymphocytes, e.g. CD8 +< T-lymphocytes, which may be detected in various proliferation or cytokine production tests in vitro.

[0327] The terms "inducing an immune response" and "eliciting an immune response" and similar terms in the context of the present disclosure refer to the induction of an immune response, such as the induction of a cellular immune response, a humoral immune response, or both. The immune response may be protective / preventive / prophylactic and / or therapeutic. The immune response may be directed against any immunogen or antigen or antigen peptide, such as against a tumor-associated antigen or a pathogen-associated antigen (e.g., an antigen of a virus (such as influenza virus (A, B, or C), CMV or RSV)). "Inducing" in this context may mean that there was no immune response against a particular antigen or pathogen before induction, but it may also mean that there was a certain level of immune response against a particular antigen or pathogen before induction and after induction said immune response is enhanced. Thus, "inducing the immune response" in this context also includes "enhancing the immune response". In some embodiments, after inducing an immune response in an individual, said individual is protected from developing a disease such as an infectious disease or a cancerous disease or the disease condition is ameliorated by inducing an immune response.

[0328] The terms "cellular immune response", "cellular response", "cell-mediated immunity" or similar terms are meant to include a cellular response directed to cells characterized by expression of an antigen and / or presentation of an antigen with class I or class II MHC. The cellular response relates to cells called T cells or T lymphocytes which act as either "helpers" or "killers". The helper T cells (also termed CD4 +< T cells) play a central role by regulating the immune response and the killer cells (also termed cytotoxic T cells, cytolytic T cells, CD8 +< T cells or CTLs) kill cells such as diseased cells.

[0329] The term "humoral immune response" refers to a process in living organisms wherein antibodies are produced in response to agents and organisms, which they ultimately neutralize and / or eliminate. The specificity of the antibody response is mediated by T and / or B cells through membrane-associated receptors that bind antigen of a single specificity. Following binding of an appropriate antigen and receipt of various other activating signals, B lymphocytes divide, which produces memory B cells as well as antibody secreting plasma cell clones, each producing antibodies that recognize the identical antigenic epitope as was recognized by its antigen receptor. Memory B lymphocytes remain dormant until they are subsequently activated by their specific antigen. These lymphocytes provide the cellular basis of memory and the resulting escalation in antibody response when re-exposed to a specific antigen.

[0330] The term "antibody" as used herein, refers to an immunoglobulin molecule, which is able to specifically bind to an epitope on an antigen. In particular, the term "antibody" refers to a glycoprotein comprising at least two heavy (H) chains and two light (L) chains inter-connected by disulfide bonds. The term "antibody" includes monoclonal antibodies, recombinant antibodies, human antibodies, humanized antibodies, chimeric antibodies and combinations of any of the foregoing. Each heavy chain is comprised of a heavy chain variable region (VH) and a heavy chain constant region (CH). Each light chain is comprised of a light chain variable region (VL) and a light chain constant region (CL). The variable regions and constant regions are also referred to herein as variable domains and constant domains, respectively. The VH and VL regions can be further subdivided into regions of hypervariability, termed complementarity determining regions (CDRs), interspersed with regions that are more conserved, termed framework regions (FRs). Each VH and VL is composed of three CDRs and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. The CDRs of a VH are termed HCDR1, HCDR2 and HCDR3, the CDRs of a VL are termed LCDR1, LCDR2 and LCDR3. The variable regions of the heavy and light chains contain a binding domain that interacts with an antigen. The constant regions of an antibody comprise the heavy chain constant region (CH) and the light chain constant region (CL), wherein CH can be further subdivided into constant domain CH1, a hinge region, and constant domains CH2 and CH3 (arranged from amino-terminus to carboxy-terminus in the following order: CH1, CH2, CH3). The constant regions of the antibodies may mediate the binding of the immunoglobulin to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component (C1q) of the classical complement system. Antibodies can be intact immunoglobulins derived from natural sources or from recombinant sources and can be immunoactive portions of intact immunoglobulins. Antibodies are typically tetramers of immunoglobulin molecules. Antibodies may exist in a variety of forms including, for example, polyclonal antibodies, monoclonal antibodies, Fv, Fab and F(ab) 2 , as well as single chain antibodies and humanized antibodies.

[0331] The term "immunoglobulin" relates to proteins of the immunoglobulin superfamily, such as to antigen receptors such as antibodies or the B cell receptor (BCR). The immunoglobulins are characterized by a structural domain, i.e., the immunoglobulin domain, having a characteristic immunoglobulin (Ig) fold. The term encompasses membrane bound immunoglobulins as well as soluble immunoglobulins. Membrane bound immunoglobulins are also termed surface immunoglobulins or membrane immunoglobulins, which are generally part of the BCR. Soluble immunoglobulins are generally termed antibodies. Immunoglobulins generally comprise several chains, typically two identical heavy chains and two identical light chains which are linked via disulfide bonds. These chains are primarily composed of immunoglobulin domains, such as the V L (variable light chain) domain, C L (constant light chain) domain, V H (variable heavy chain) domain, and the C H (constant heavy chain) domains C H 1, C H 2, C H 3, and C H 4. There are five types of mammalian immunoglobulin heavy chains, i.e., α, δ, ε, γ, and µ which account for the different classes of antibodies, i.e., IgA, IgD, IgE, IgG, and IgM. As opposed to the heavy chains of soluble immunoglobulins, the heavy chains of membrane or surface immunoglobulins comprise a transmembrane domain and a short cytoplasmic domain at their carboxy-terminus. In mammals there are two types of light chains, i.e., lambda and kappa. The immunoglobulin chains comprise a variable region and a constant region. The constant region is essentially conserved within the different isotypes of the immunoglobulins, wherein the variable part is highly divers and accounts for antigen recognition.

[0332] The terms "vaccination" and "immunization" describe the process of treating an individual for therapeutic or prophylactic reasons and relate to the procedure of administering one or more immunogen(s) or antigen(s) or derivatives thereof, in particular in the form of RNA (especially mRNA) coding therefor, as described herein to an individual and stimulating an immune response against said one or more immunogen(s) or antigen(s) or cells characterized by presentation of said one or more immunogen(s) or antigen(s).

[0333] By "cell characterized by presentation of an antigen" or "cell presenting an antigen" or "MHC molecules which present an antigen on the surface of an antigen presenting cell" or similar expressions is meant a cell such as a diseased cell, in particular a tumor cell or an infected cell, or an antigen presenting cell presenting the antigen or an antigen peptide, either directly or following processing, in the context of MHC molecules, such as MHC class I and / or MHC class II molecules. In some embodiments, the MHC molecules are MHC class I molecules.

[0334] The term "allergen" refers to a kind of antigen which originates from outside the body of a subject (i.e., the allergen can also be called "heterologous antigen") and which produces an abnormally vigorous immune response in which the immune system of the subject fights off a perceived threat that would otherwise be harmless to the subject. "Allergies" are the diseases caused by such vigorous immune reactions against allergens. An allergen usually is an antigen which is able to stimulate a type-I hypersensitivity reaction in atopic individuals through immunoglobulin E (IgE) responses. Particular examples of allergens include allergens derived from peanut proteins (e.g., Ara h 2.02), ovalbumin, grass pollen proteins (e.g., Phl p 5), and proteins of dust mites (e.g., Der p 2).

[0335] The term "growth factors" refers to molecules which are able to stimulate cellular growth, proliferation, healing, and / or cellular differentiation. Typically, growth factors act as signaling molecules between cells. The term "growth factors" include particular cytokines and hormones which bind to specific receptors on the surface of their target cells. Examples of growth factors include bone morphogenetic proteins (BMPs), fibroblast growth factors (FGFs), vascular endothelial growth factors (VEGFs), such as VEGFA, epidermal growth factor (EGF), insulin-like growth factor, ephrins, macrophage colony-stimulating factor, granulocyte colony-stimulating factor, granulocyte macrophage colony-stimulating factor, neuregulins, neurotrophins (e.g., brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF)), placental growth factor (PGF), platelet-derived growth factor (PDGF), renalase (RNLS) (anti-apoptotic survival factor), T-cell growth factor (TCGF), thrombopoietin (TPO), transforming growth factors (transforming growth factor alpha (TGF-α), transforming growth factor beta (TGF-β)), and tumor necrosis factor-alpha (TNF-α). In some embodiments, a "growth factor" is a peptide or polypeptide growth factor.

[0336] The term "protease inhibitors" refers to molecules, in particular peptides or polypeptides, which inhibit the function of proteases. Protease inhibitors can be classified by the protease which is inhibited (e.g., aspartic protease inhibitors) or by their mechanism of action (e.g., suicide inhibitors, such as serpins). Particular examples of protease inhibitors include serpins, such as alpha 1-antitrypsin, aprotinin, and bestatin.

[0337] The term "enzymes" refers to macromolecular biological catalysts which accelerate chemical reactions. Like any catalyst, enzymes are not consumed in the reaction they catalyze and do not alter the equilibrium of said reaction. Unlike many other catalysts, enzymes are much more specific. In some embodiments, an enzyme is essential for homeostasis of a subject, e.g., any malfunction (in particular, decreased activity which may be caused by any of mutation, deletion or decreased production) of the enzyme results in a disease. Examples of enzymes include herpes simplex virus type 1 thymidine kinase (HSV1-TK), hexosaminidase, phenylalanine hydroxylase, pseudocholinesterase, and lactase.

[0338] The term "receptors" refers to protein molecules which receive signals (in particular chemical signals called ligands) from outside a cell. The binding of a signal (e.g., ligand) to a receptor causes some kind of response of the cell, e.g., the intracellular activation of a kinase. Receptors include transmembrane receptors (such as ion channel-linked (ionotropic) receptors, G protein-linked (metabotropic) receptors, and enzyme-linked receptors) and intracellular receptors (such as cytoplasmic receptors and nuclear receptors). Particular examples of receptors include steroid hormone receptors, growth factor receptors, and peptide receptors (i.e., receptors whose ligands are peptides), such as P-selectin glycoprotein ligand-1 (PSGL-1). The term "growth factor receptors" refers to receptors which bind to growth factors.

[0339] The term "apoptosis regulators" refers to molecules, in particular peptides or polypeptides, which modulate apoptosis, i.e., which either activate or inhibit apoptosis. Apoptosis regulators can be grouped into two broad classes: those which modulate mitochondrial function and those which regulate caspases. The first class includes proteins (e.g., BCL-2, BCL-xL) which act to preserve mitochondrial integrity by preventing loss of mitochondrial membrane potential and / or release of pro-apoptotic proteins such as cytochrome C into the cytosol. Also to this first class belong proapoptotic proteins (e.g., BAX, BAK, BIM) which promote release of cytochrome C. The second class includes proteins such as the inhibitors of apoptosis proteins (e.g., XIAP) or FLIP which block the activation of caspases.

[0340] The term "transcription factors" relates to proteins which regulate the rate of transcription of genetic information from DNA to messenger RNA, in particular by binding to a specific DNA sequence. Transcription factors may regulate cell division, cell growth, and cell death throughout life; cell migration and organization during embryonic development; and / or in response to signals from outside the cell, such as a hormone. Transcription factors contain at least one DNA-binding domain which binds to a specific DNA sequence, usually adjacent to the genes which are regulated by the transcription factors. Particular examples of transcription factors include MECP2, FOXP2, FOXP3, the STAT protein family, and the HOX protein family.

[0341] The term "tumor suppressor proteins" relates to molecules, in particular peptides or polypeptides, which protect a cell from one step on the path to cancer. Tumor-suppressor proteins (usually encoded by corresponding tumor-suppressor genes) exhibit a weakening or repressive effect on the regulation of the cell cycle and / or promote apoptosis. Their functions may be one or more of the following: repression of genes essential for the continuing of the cell cycle; coupling the cell cycle to DNA damage (as long as damaged DNA is present in a cell, no cell division should take place); initiation of apoptosis, if the damaged DNA cannot be repaired; metastasis suppression (e.g., preventing tumor cells from dispersing, blocking loss of contact inhibition, and inhibiting metastasis); and DNA repair. Particular examples of tumor-suppressor proteins include p53, phosphatase and tensin homolog (PTEN), SWI / SNF (SWitch / Sucrose Non-Fermentable), von Hippel-Lindau tumor suppressor (pVHL), adenomatous polyposis coli (APC), CD95, suppression of tumorigenicity 5 (ST5), suppression of tumorigenicity 5 (ST5), suppression of tumorigenicity 14 (ST14), and Yippee-like 3 (YPEL3). The term "structural proteins" refers to proteins which confer stiffness and rigidity to otherwise-fluid biological components. Structural proteins are mostly fibrous (such as collagen and elastin) but may also be globular (such as actin and tubulin). Usually, globular proteins are soluble as monomers, but polymerize to form long, fibers which, for example, may make up the cytoskeleton. Other structural proteins are motor proteins (such as myosin, kinesin, and dynein) which are capable of generating mechanical forces, and surfactant proteins. Particular examples of structural proteins include collagen, surfactant protein A, surfactant protein B, surfactant protein C, surfactant protein D, elastin, tubulin, actin, and myosin.

[0342] The term "reprogramming factors" or "reprogramming transcription factors" relates to molecules, in particular peptides or polypeptides, which, when expressed in somatic cells optionally together with further agents such as further reprogramming factors, lead to reprogramming or de-differentiation of said somatic cells to cells having stem cell characteristics, in particular pluripotency. Particular examples of reprogramming factors include OCT4, SOX2, c-MYC, KLF4, LIN28, and NANOG.

[0343] The term "genomic engineering proteins" relates to proteins which are able to insert, delete or replace DNA in the genome of a subject. Particular examples of genomic engineering proteins include meganucleases, zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly spaced short palindromic repeat-CRISPR-associated protein 9 (CRISPR-Cas9).

[0344] The term "blood proteins" relates to peptides or polypeptides which are present in blood plasma of a subject, in particular blood plasma of a healthy subject. Blood proteins have diverse functions such as transport (e.g., albumin, transferrin), enzymatic activity (e.g., thrombin or ceruloplasmin), blood clotting (e.g., fibrinogen), defense against pathogens (e.g., complement components and immunoglobulins), protease inhibitors (e.g., alpha 1-antitrypsin), etc. Particular examples of blood proteins include thrombin, serum albumin, Factor Vil, Factor VIII, insulin, Factor IX, Factor X, tissue plasminogen activator, protein C, von Willebrand factor, antithrombin III, glucocerebrosidase, erythropoietin, granulocyte colony stimulating factor (G-CSF), modified Factor VIII, and anticoagulants.

[0345] Thus, in some embodiments, the pharmaceutically active peptide or polypeptide is (i) a cytokine, preferably selected from the group consisting of erythropoietin (EPO), interleukin 4 (IL-2), and interleukin 10 (IL-11), more preferably EPO; (ii) an adhesion molecule, in particular an integrin; (iii) an immunoglobulin, in particular an antibody; (iv) an immunologically active compound, in particular an antigen, such as a viral or bacterial antigen, e.g., an antigen of SARS-CoV-2; (v) a hormone, in particular vasopressin, insulin or growth hormone; (vi) a growth factor, in particular VEGFA; (vii) a protease inhibitor, in particular alpha 1-antitrypsin; (viii) an enzyme, preferably selected from the group consisting of herpes simplex virus type 1 thymidine kinase (HSV1-TK), hexosaminidase, phenylalanine hydroxylase, pseudocholinesterase, pancreatic enzymes, and lactase; (ix) a receptor, in particular growth factor receptors; (x) an apoptosis regulator, in particular BAX; (xi) a transcription factor, in particular FOXP3; (xii) a tumor suppressor protein, in particular p53; (xiii) a structural protein, in particular surfactant protein B; (xiv) a reprogramming factor, e.g., selected from the group consisting of OCT4, SOX2, c-MYC, KLF4, LIN28 and NANOG; (xv) a genomic engineering protein, in particular clustered regularly spaced short palindromic repeat-CRISPR-associated protein 9 (CRISPR-Cas9); and (xvi) a blood protein, in particular fibrinogen.

[0346] In some embodiments, a pharmaceutically active peptide or polypeptide comprises one or more antigens or one or more epitopes, i.e., administration of the peptide or polypeptide to a subject elicits an immune response against the one or more antigens or one or more epitopes in a subject which may be therapeutic or partially or fully protective.

[0347] In some embodiments, the RNA encodes at least one epitope, e.g., at least two epitopes, at least three epitopes, at least four epitopes, at least five epitopes, at least six epitopes, at least seven epitopes, at least eight epitopes, at least nine epitopes, or at least ten epitopes.

[0348] In some embodiments, the target antigen is a tumor antigen and the antigenic sequence (e.g., an epitope) is derived from the tumor antigen. The tumor antigen may be a "standard" antigen, which is generally known to be expressed in various cancers. The tumor antigen may also be a "neo-antigen", which is specific to an individual's tumor and has not been previously recognized by the immune system. A neo-antigen or neo-epitope may result from one or more cancer-specific mutations in the genome of cancer cells resulting in amino acid changes. If the tumor antigen is a neo-antigen, the vaccine antigen preferably comprises an epitope or a fragment of said neo-antigen comprising one or more amino acid changes.

[0349] Examples of tumor antigens include, without limitation, p53, ART-4, BAGE, beta-catenin / m, Bcr-abL CAMEL, CAP-1 , CASP-8, CDC27 / m, CDK4 / m, CEA, the cell surface proteins of the claudin family, such as CLAUDIN-6, CLAUDIN-18.2 and CLAUDIN-12, c-MYC, CT, Cyp-B, DAM, ELF2M, ETV6-AML1, G250, GAGE, GnT-V, Gap 100, HAGE, HER-2 / neu, HPV-E7, HPV-E6, HAST-2, hTERT (or hTRT), LAGE, LDLR / FUT, MAGE-A, preferably MAGE-A1 , MAGE-A2, MAGE- A3, MAGE-A4, MAGE-A5, MAGE-A6, MAGE-A7, MAGE-A8, MAGE-A9, MAGE-A 10, MAGE-A 11, or MAGE-A12, MAGE-B, MAGE-C, MART- 1 / Melan-A, MC1R, Myosin / m, MUC1, MUM-1, MUM-2, MUM-3, NA88-A, NF1 , NY-ESO-1 , NY-BR-1 , pl90 minor BCR-abL, Pml / RARa, PRAME, proteinase 3, PSA, PSM, RAGE, RU1 or RU2, SAGE, SART-1 or SART-3, SCGB3A2, SCP1, SCP2, SCP3, SSX, SURVIVIN, TEL / AML1, TPI / m, TRP-1 , TRP-2, TRP-2 / INT2, TPTE, WT, and WT-1. Cancer mutations vary with each individual. Thus, cancer mutations that encode novel epitopes (neo-epitopes) represent attractive targets in the development of vaccine compositions and immunotherapies. The efficacy of tumor immunotherapy relies on the selection of cancer-specific antigens and epitopes capable of inducing a potent immune response within a host. RNA can be used to deliver patient-specific tumor epitopes to a patient. Dendritic cells (DCs) residing in the spleen represent antigen-presenting cells of particular interest for RNA expression of immunogenic epitopes or antigens such as tumor epitopes. The use of multiple epitopes has been shown to promote therapeutic efficacy in tumor vaccine compositions. Rapid sequencing of the tumor mutanome may provide multiple epitopes for individualized vaccines which can be encoded by RNA (in particular, mRNA) described herein, e.g., as a single polypeptide wherein the epitopes are optionally separated by linkers. In some embodiments of the present disclosure, the RNA (in particular, mRNA) encodes at least one epitope, at least two epitopes, at least three epitopes, at least four epitopes, at least five epitopes, at least six epitopes, at least seven epitopes, at least eight epitopes, at least nine epitopes, or at least ten epitopes. Exemplary embodiments include RNA (in particular, mRNA) that encodes at least five epitopes (termed a "pentatope") and RNA (in particular, mRNA) that encodes at least ten epitopes (termed a "decatope").

[0350] In some embodiments, the antigen or epitope is derived from a pathogen-associated antigen, in particular from a viral antigen.

[0351] In some embodiments, the antigen or epitope is derived from a coronavirus protein, an immunogenic variant thereof, or an immunogenic fragment of the coronavirus protein or the immunogenic variant thereof. Thus, in some embodiments, the mRNA used in the present disclosure encodes an amino acid sequence comprising a coronavirus protein, an immunogenic variant thereof, or an immunogenic fragment of the coronavirus protein or the immunogenic variant thereof.

[0352] In some embodiments, the antigen or epitope is derived from a coronavirus S protein, an immunogenic variant thereof, or an immunogenic fragment of the coronavirus S protein or the immunogenic variant thereof. Thus, in some embodiments, the RNA (in particular, mRNA) described in the present disclosure encodes an amino acid sequence comprising a coronavirus S protein, an immunogenic variant thereof, or an immunogenic fragment of the coronavirus S protein or the immunogenic variant thereof. In some embodiments, the coronavirus is MERS-CoV. In some embodiments, the coronavirus is SARS-CoV. In some embodiments, the coronavirus is SARS-CoV-2.

[0353] Coronaviruses are enveloped, positive-sense, single-stranded RNA ((+) ssRNA) viruses. They have the largest genomes (26-32 kb) among known RNA viruses and are phylogenetically divided into four genera (α, β, γ, and δ), with betacoronaviruses further subdivided into four lineages (A, B, C, and D). Coronaviruses infect a wide range of avian and mammalian species, including humans. Some human coronaviruses generally cause mild respiratory diseases, although severity can be greater in infants, the elderly, and the immunocompromised. Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus (SARS-CoV), belonging to betacoronavirus lineages C and B, respectively, are highly pathogenic. Both viruses emerged into the human population from animal reservoirs within the last 15 years and caused outbreaks with high case-fatality rates. The outbreak of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) that causes atypical pneumonia (coronavirus disease 2019; COVID-19) has raged in China since mid-December 2019, and has developed to be a public health emergency of international concern. SARS-CoV-2 (MN908947.3) belongs to betacoronavirus lineage B. It has at least 70% sequence similarity to SARS-CoV.

[0354] In general, coronaviruses have four structural proteins, namely, envelope (E), membrane (M), nucleocapsid (N), and spike (S). The E and M proteins have important functions in the viral assembly, and the N protein is necessary for viral RNA synthesis. The critical glycoprotein S is responsible for virus binding and entry into target cells. The S protein is synthesized as a single-chain inactive precursor that is cleaved by furin-like host proteases in the producing cell into two noncovalently associated subunits, S1 and S2. The S1 subunit contains the receptor-binding domain (RBD), which recognizes the host-cell receptor. The S2 subunit contains the fusion peptide, two heptad repeats, and a transmembrane domain, all of which are required to mediate fusion of the viral and host-cell membranes by undergoing a large conformational rearrangement. The S1 and S2 subunits trimerize to form a large prefusion spike.

[0355] The S precursor protein of SARS-CoV-2 can be proteolytically cleaved into S1 (685 aa) and S2 (588 aa) subunits. The S1 subunit comprises the receptor-binding domain (RBD), which mediates virus entry into sensitive cells through the host angiotensin-converting enzyme 2 (ACE2) receptor.

[0356] In some embodiments, the antigen or epitope is derived from a SARS-CoV-2 S protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof. In some embodiments, the RNA (in particular, mRNA) described in the present disclosure encodes an amino acid sequence comprising a SARS-CoV-2 S protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof. Thus, in some embodiments, the encoded amino acid sequence comprises an epitope of SARS-CoV-2 S protein or an immunogenic variant thereof for inducing an immune response against coronavirus S protein, in particular SARS-CoV-2 S protein in a subject. In some embodiments, RNA (in particular, mRNA) is administered to provide (following expression by appropriate target cells) antigen for induction of an immune response, e.g., antibodies and / or immune effector cells, which is targeted to target antigen (coronavirus S protein, in particular SARS-CoV-2 S protein) or a procession product thereof. In some embodiments, the immune response which is to be induced according to the present disclosure is a B cell-mediated immune response, i.e., an antibody-mediated immune response. Additionally or alternatively, in some embodiments, the immune response which is to be induced according to the present disclosure is a T cell-mediated immune response. In some embodiments, the immune response is an anti-coronavirus, in particular anti-SARS-CoV-2 immune response.

[0357] SARS-CoV-2 coronavirus full length spike (S) protein consist of 1273 amino acids and has the following amino acid sequence:

[0358] For purposes of the present disclosure, the above sequence is considered the wild-type SARS-CoV-2 S protein amino acid sequence. Position numberings in SARS-CoV-2 S protein given herein are in relation to the amino acid sequence according to SEQ ID NO: 11 and corresponding positions in SARS-CoV-2 S protein variants.

[0359] In specific embodiments, full length spike (S) protein according to SEQ ID NO: 11 is modified in such a way that the prototypical prefusion conformation is stabilized. Stabilization of the prefusion conformation may be obtained by introducing two consecutive proline substitutions at amino acid residues 986 and 987 in the full-length spike protein. Specifically, spike (S) protein stabilized protein variants are obtained in a way that the amino acid residue at position 986 is exchanged to proline and the amino acid residue at position 987 is also exchanged to proline. In one embodiment, a SARS-CoV-2 S protein variant wherein the prototypical prefusion conformation is stabilized comprises the following amino acid sequence:

[0360] Those skilled in the art are aware of various spike variants, and / or resources that document them.

[0361] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) encodes an amino acid sequence which comprises, consists essentially of or consists of a spike (S) protein of SARS-CoV-2, a variant thereof, or a fragment thereof.

[0362] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 11 or 12, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 11 or 12, or an immunogenic fragment of the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 11 or 12, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 11 or 12. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 11 or 12.

[0363] In some embodiments, the encoded amino acid sequence comprises, consists essentially of or consists of SARS-CoV-2 spike S1 fragment (S1) (the S1 subunit of a spike protein (S) of SARS-CoV-2), a variant thereof, or a fragment thereof.

[0364] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 17 to 683 of SEQ ID NO: 11, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 17 to 683 of SEQ ID NO: 11, or an immunogenic fragment of the amino acid sequence of amino acids 17 to 683 of SEQ ID NO: 11, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 17 to 683 of SEQ ID NO: 11. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 17 to 683 of SEQ ID NO: 11.

[0365] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 17 to 685 of SEQ ID NO: 11, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 17 to 685 of SEQ ID NO: 11, or an immunogenic fragment of the amino acid sequence of amino acids 17 to 685 of SEQ ID NO: 11, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 17 to 685 of SEQ ID NO: 11. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 17 to 685 of SEQ ID NO: 11.

[0366] In some embodiments, the encoded amino acid sequence comprises, consists essentially of or consists of the receptor binding domain (RBD) of the S1 subunit of a spike protein (S) of SARS-CoV-2, a variant thereof, or a fragment thereof. The amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11, a variant thereof, or a fragment thereof is also referred to herein as "RBD" or "RBD domain".

[0367] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11, or an immunogenic fragment of the amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11.

[0368] According to certain embodiments, a signal peptide is fused, either directly or through a linker, to a SARS-CoV-2 S protein, a variant thereof, or a fragment thereof, i.e., the antigenic peptide or protein. Accordingly, in some embodiments, a signal peptide is fused to the above described amino acid sequences derived from SARS-CoV-2 S protein or immunogenic fragments thereof (antigenic peptides or proteins) comprised by the encoded amino acid sequences described above.

[0369] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 11 or 12, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 11 or 12, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 11 or 12, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 11 or 12. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 11 or 12.

[0370] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 1 to 683 of SEQ ID NO: 11, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 1 to 683 of SEQ ID NO: 11, or an immunogenic fragment of the amino acid sequence of amino acids 1 to 683 of SEQ ID NO: 11, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 1 to 683 of SEQ ID NO: 11. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 1 to 683 of SEQ ID NO: 11.

[0371] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 1 to 685 of SEQ ID NO: 11, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 1 to 685 of SEQ ID NO: 11, or an immunogenic fragment of the amino acid sequence of amino acids 1 to 685 of SEQ ID NO: 11, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 1 to 685 of SEQ ID NO: 11. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of amino acids 1 to 685 of SEQ ID NO: 11.

[0372] According to certain embodiments, a trimerization domain is fused, either directly or through a linker, e.g., a glycine / serine linker, to a SARS-CoV-2 S protein, a variant thereof, or a fragment thereof, i.e., the antigenic peptide or protein. Accordingly, in some embodiments, a trimerization domain is fused to the above described amino acid sequences derived from SARS-CoV-2 S protein or immunogenic fragments thereof (antigenic peptides or proteins) comprised by the encoded amino acid sequences described above (which may optionally be fused to a signal peptide as described above).

[0373] Such trimerization domains are preferably located at the C-terminus of the antigenic peptide or protein, without being limited thereto. Trimerization domains as defined herein preferably allow the trimerization of the antigenic peptide or protein as encoded by the RNA. Examples of trimerization domains as defined herein include, without being limited thereto, foldon, the natural trimerization domain of T4 fibritin. The C-terminal domain of T4 fibritin (foldon) is obligatory for the formation of the fibritin trimer structure and can be used as an artificial trimerization domain. In some embodiments, the trimerization domain as defined herein includes, without being limited thereto, a sequence comprising the amino acid sequence of SEQ ID NO: 13 or a functional variant thereof.

[0374] In some embodiments, a trimerization domain comprises the amino acid sequence of amino acids 3 to 29 of SEQ ID NO: 13, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 3 to 29 of SEQ ID NO: 13, or a functional fragment of the amino acid sequence of amino acids 3 to 29 of SEQ ID NO: 13, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 3 to 29 of SEQ ID NO: 13. In some embodiments, a trimerization domain comprises the amino acid sequence of amino acids 3 to 29 of SEQ ID NO: 13.

[0375] In some embodiments, a trimerization domain comprises the amino acid sequence SEQ ID NO: 13, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 13, or a functional fragment of the amino acid sequence of SEQ ID NO: 13, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 13. In some embodiments, a trimerization domain comprises the amino acid sequence of SEQ ID NO: 13. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 14, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 14, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 14, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 14. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 14.

[0376] According to certain embodiments, a transmembrane domain is fused, either directly or through a linker, e.g., a glycine / serine linker, to a SARS-CoV-2 S protein, a variant thereof, or a fragment thereof, i.e., the antigenic peptide or protein. Accordingly, in some embodiments, a transmembrane domain is fused to the above described amino acid sequences derived from SARS-CoV-2 S protein or immunogenic fragments thereof (antigenic peptides or proteins) comprised by the encoded amino acid sequences described above (which may optionally be fused to a signal peptide and / or trimerization domain as described above). Such transmembrane domains are preferably located at the C-terminus of the antigenic peptide or protein, without being limited thereto. Preferably, such transmembrane domains are located at the C-terminus of the trimerization domain, if present, without being limited thereto. In some embodiments, a trimerization domain is present between the SARS-CoV-2 S protein, a variant thereof, or a fragment thereof, i.e., the antigenic peptide or protein, and the transmembrane domain. Transmembrane domains as defined herein preferably allow the anchoring into a cellular membrane of the antigenic peptide or protein as encoded by the RNA. In some embodiments, the transmembrane domain sequence as defined herein includes, without being limited thereto, the transmembrane domain sequence of SARS-CoV-2 S protein, in particular a sequence comprising the amino acid sequence of amino acids 1207 to 1254 of SEQ ID NO: 11 or a functional variant thereof. In some embodiments, a transmembrane domain sequence comprises the amino acid sequence of amino acids 1207 to 1254 of SEQ ID NO: 11, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 1207 to 1254 of SEQ ID NO: 11, or a functional fragment of the amino acid sequence of amino acids 1207 to 1254 of SEQ ID NO: 11, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of amino acids 1207 to 1254 of SEQ ID NO: 11. In some embodiments, a transmembrane domain sequence comprises the amino acid sequence of amino acids 1207 to 1254 of SEQ ID NO: 11.

[0377] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 15, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 15, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 15, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 15. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 15.

[0378] In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 16, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 16, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 16, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 16. In some embodiments, the encoded amino acid sequence comprises the amino acid sequence of SEQ ID NO: 16.

[0379] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 17, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 17, or a fragment of the nucleotide sequence of SEQ ID NO: 17, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 17; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 12, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 12, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 12, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 12. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 17; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 12.

[0380] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 17, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 17, or a fragment of the nucleotide sequence of SEQ ID NO: 17, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 17; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 12, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 12, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 12, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 12. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 17; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 12.

[0381] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 18, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 18, or a fragment of the nucleotide sequence of SEQ ID NO: 18, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 18; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 14, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 14, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 14, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 14. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 18; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 14.

[0382] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 18, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 18, or a fragment of the nucleotide sequence of SEQ ID NO: 18, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 18; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 14, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 14, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 14, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 14. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 18; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 14.

[0383] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 19, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 19, or a fragment of the nucleotide sequence of SEQ ID NO: 19, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 19; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 15, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 15, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 15, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 15. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 19; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 15.

[0384] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 19, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 19, or a fragment of the nucleotide sequence of SEQ ID NO: 19, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 19; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 15, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 15, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 15, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 15. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 19; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 15.

[0385] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 20, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 20, or a fragment of the nucleotide sequence of SEQ ID NO: 20, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 20; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 16, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 16, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 16, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 16. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) (i) comprises the nucleotide sequence of SEQ ID NO: 20; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 16. In some embodiments, RNA is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 20, a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 20, or a fragment of the nucleotide sequence of SEQ ID NO: 20, or the nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 20; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 16, an amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 16, or an immunogenic fragment of the amino acid sequence of SEQ ID NO: 16, or the amino acid sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the amino acid sequence of SEQ ID NO: 16. In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) is nucleoside modified messenger RNA (modRNA) and (i) comprises the nucleotide sequence of SEQ ID NO: 20; and / or (ii) encodes an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 16.

[0386] In some embodiments, RNA (in particular, mRNA) described herein (e.g., contained in the compositions / formulations of the present disclosure and / or used in the methods of the present disclosure) comprises BNT162b2. BNT162b2 is an mRNA vaccine for prevention of COVID-19 and demonstrated an efficacy of 95% or more at preventing COVID-19. The vaccine is made of a 5'capped mRNA encoding for the full-length SARS-CoV-2 spike glycoprotein (S) encapsulated in lipid nanoparticles (LNPs). The RNA may be presented as a product containing BNT162b2 as active substance and other ingredients comprising: a cationically ionizable lipid (in particular, a compound of formula (I)); a polymer-conjugated lipid, preferably selected from the groups consisting of a sarcosinylated lipid and a pegylated lipid; 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC); and cholesterol. The sequence of the S protein was chosen based on the sequence for the "SARS-CoV-2 isolate Wuhan-Hu -1": GenBank: MN908947.3 (complete genome) and GenBank: QHD43416.1 (spike surface glycoprotein). The active substance consists of a single-stranded, 5'-capped codon-optimized mRNA that is translated into the spike antigen of SARS-CoV-2. The protein sequence contains two proline mutations, which ensure an antigenically optimal pre-fusion confirmation (P2 S). The RNA does not contain any uridines; instead of uridine the modified N1-methylpseudouridine is used in RNA synthesis. The RNA contains common structural elements optimized for mediating high RNA stability and translational efficiency. The LNPs protect the RNA from degradation by RNAses and enable transfection of host cells after intramuscular (IM) delivery. The mRNA is translated into the SARS-CoV-2 S protein in the host cell. The S protein is then expressed on the cell surface where it induces an adaptive immune response. The S protein is identified as a target for neutralising antibodies against the virus and is therefore considered a relevant vaccine component. BNT162b2 is administered to adults intramuscularly (IM) in two 30 µg doses given 21 days apart.

[0387] In some embodiments, the RNA (in particular, mRNA) described herein is a modified RNA, in particular a stabilized mRNA. In some embodiments, the RNA comprises a modified nucleoside in place of at least one uridine. In some embodiments, the RNA comprises a modified nucleoside in place of each uridine. In some embodiments, the modified nucleoside is independently selected from pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine (m5U).

[0388] In some embodiments, the RNA (in particular, mRNA) described herein comprises a modified nucleoside in place of uridine.

[0389] In some embodiments, the modified nucleoside is selected from pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine (m5U).

[0390] In some embodiments, the RNA (in particular, mRNA) described herein comprises a 5' cap. In some embodiments, m 2 7,3'-O< Gppp(m 1 2'-O< ) ApG is utilized as specific capping structure at the 5'-end of the mRNA.

[0391] In some embodiments, the RNA (in particular, mRNA) encoding an amino acid sequence comprising a SARS-CoV-2 S protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof comprises a 5' UTR comprising the nucleotide sequence of SEQ ID NO: 6, or a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 6.

[0392] In some embodiments, the RNA (in particular, mRNA) encoding an amino acid sequence comprising a SARS-CoV-2 S protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof comprises a 3' UTR comprising the nucleotide sequence of SEQ ID NO: 7, or a nucleotide sequence having at least 99%, 98%, 97%, 96%, 95%, 90%, 85%, or 80% identity to the nucleotide sequence of SEQ ID NO: 7.

[0393] In some embodiments, the RNA (in particular, mRNA) encoding an amino acid sequence comprising a SARS-CoV-2 S protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof comprises a poly-A sequence.

[0394] In some embodiments, the poly-A sequence comprises at least 100 nucleotides.

[0395] In some embodiments, the poly-A sequence comprises or consists of the nucleotide sequence of SEQ ID NO: 8.

[0396] In some embodiments, the RNA (in particular, mRNA) described herein is formulated or is to be formulated as a liquid, a solid, or a combination thereof.

[0397] In some embodiments, the RNA (in particular, mRNA) described herein is formulated or is to be formulated for injection.

[0398] In some embodiments, the RNA (in particular, mRNA) described herein is formulated or is to be formulated for intramuscular administration.

[0399] In some embodiments, the RNA (in particular, mRNA) described herein is formulated or is to be formulated as a composition, e.g., a pharmaceutical composition.

[0400] In some embodiments, the composition comprises a cationically ionizable lipid of formula (I) (or of any one of the formulas (Ia), (Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (IIa), (IIb), (IIIa), (IIIb), (IV-1), (IV-2), and (IV-3)).

[0401] In some embodiments, the composition comprises a cationically ionizable lipid of formula (I) (or of any one of the formulas (Ia), (Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (IIa), (IIb), (IIIa), (Illb), (IV-1), (IV-2), and (IV-3)) and one or more additional lipids. In some embodiments, the one or more additional lipids are selected from polymer-conjugated lipids, neutral lipids, and combinations thereof. In some embodiments, the neutral lipids include phospholipids, steroid lipids, and combinations thereof. In some embodiments, the one or more additional lipids are a combination of a polymer-conjugated lipid, a phospholipid, and a steroid lipid.

[0402] In some embodiments, the composition comprises a cationically ionizable lipid of formula (I) (or of any one of the formulas (la), (Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (IIa), (IIb), (IIIa), (IIIb), (IV-1), (IV-2), and (IV-3)); a polymer-conjugated lipid selected from the group consisting of a polysarcosine-conjugated lipid as disclosed herein; and cholesterol.

[0403] In some embodiments, the composition comprises a cationically ionizable lipid of formula (I) (or of any one of the formulas (Ia), (Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (IIa), (IIb), (IIIa), (IIIb), (IV-1), (IV-2), and (IV-3)); a polymer-conjugated lipid selected from the group consisting of a polysarcosine-conjugated lipid as disclosed herein; cholesterol; and a phospholipid. In some embodiments, the phospholipid is DSPC. In some embodiments, the phospholipid is DOPE.

[0404] In some embodiments, the composition comprises a cationically ionizable lipid of formula (IV-1), (IV-2), or (IV-3); a polymer-conjugated lipid selected from the group consisting of DMG-PEG 2000 and C14pSar23; cholesterol; and a phospholipid. In some embodiments, the phospholipid is DSPC. In some embodiments, the phospholipid is DOPE.

[0405] In some embodiments, the RNA is mRNA or saRNA.

[0406] In some embodiments, at least a portion of (i) the RNA, (ii) the cationically ionizable lipid, and if present, (iii) the one or more additional lipids is present in particles. In some embodiments, the particles are nanoparticles, such as lipid nanoparticles (LNPs).

[0407] In some embodiments, the composition, in particular the pharmaceutical composition, is a vaccine.

[0408] In some embodiments, the composition, in particular the pharmaceutical composition, further comprises one or more pharmaceutically acceptable carriers, diluents and / or excipients.

[0409] In some embodiments, the RNA and / or the composition, in particular the pharmaceutical composition, is / are a component of a kit.

[0410] In some embodiments, the kit further comprises instructions for use of the RNA for inducing an immune response against coronavirus in a subject.

[0411] In some embodiments, the kit further comprises instructions for use of the RNA for therapeutically or prophylactically treating a coronavirus infection in a subject.

[0412] In some embodiments, the subject is a human.

[0413] In some embodiments, the coronavirus is a betacoronavirus.

[0414] In some embodiments, the coronavirus is a sarbecovirus.

[0415] In some embodiments, the coronavirus is SARS-CoV-2.

[0416] The term "immunologically equivalent" means that the immunologically equivalent molecule such as the immunologically equivalent amino acid sequence exhibits the same or essentially the same immunological properties and / or exerts the same or essentially the same immunological effects, e.g., with respect to the type of the immunological effect. In the context of the present disclosure, the term "immunologically equivalent" is preferably used with respect to the immunological effects or properties of antigens or antigen variants used for immunization. For example, an amino acid sequence is immunologically equivalent to a reference amino acid sequence if said amino acid sequence when exposed to the immune system of a subject induces an immune reaction having a specificity of reacting with the reference amino acid sequence. Thus, in some embodiments, a molecule which is immunologically equivalent to an antigen exhibits the same or essentially the same properties and / or exerts the same or essentially the same effects regarding the stimulation, priming and / or expansion of T cells as the antigen to which the T cells are targeted.

[0417] In some embodiments, the RNA (in particular, mRNA), e.g., RNA encoding vaccine antigen, described in the present disclosure is non-immunogenic. RNA encoding an immunostimulant may be administered according to the present disclosure to provide an adjuvant effect. The RNA encoding an immunostimulant may be standard RNA or non-immunogenic RNA.

[0418] The term "non-immunogenic RNA" (such as "non-immunogenic mRNA") as used herein refers to RNA that does not induce a response by the immune system upon administration, e.g., to a mammal, or induces a weaker response than would have been induced by the same RNA that differs only in that it has not been subjected to the modifications and treatments that render the non-immunogenic RNA non-immunogenic, i.e., than would have been induced by standard RNA (stdRNA). In certain embodiments, non-immunogenic RNA, which is also termed modified RNA (modRNA) herein, is rendered non-immunogenic by incorporating modified nucleosides suppressing RNA-mediated activation of innate immune receptors into the RNA and / or limiting the amount of double-stranded RNA (dsRNA), e.g., by limiting the formation of double-stranded RNA (dsRNA), e.g., during in vitro transcription, and / or by removing double-stranded RNA (dsRNA), e.g., following in vitro transcription. In certain embodiments, non-immunogenic RNA is rendered non-immunogenic by incorporating modified nucleosides suppressing RNA-mediated activation of innate immune receptors into the RNA and / or by removing double-stranded RNA (dsRNA), e.g., following in vitro transcription.

[0419] For rendering the non-immunogenic RNA (especially mRNA) non-immunogenic by the incorporation of modified nucleosides, any modified nucleoside may be used as long as it lowers or suppresses immunogenicity of the RNA. Particularly preferred are modified nucleosides that suppress RNA-mediated activation of innate immune receptors. In some embodiments, the modified nucleosides comprise a replacement of one or more uridines with a nucleoside comprising a modified nucleobase. In some embodiments, the modified nucleobase is a modified uracil. In some embodiments, the nucleoside comprising a modified nucleobase is selected from the group consisting of 3-methyl-uridine (m 3< U), 5-methoxy-uridine (mo 5< U), 5-aza-uridine, 6-aza-uridine, 2-thio-5-aza-uridine, 2-thio-uridine (s 2< U), 4-thio-uridine (s 4< U), 4-thio-pseudouridine, 2-thio-pseudouridine, 5-hydroxy-uridine (ho 5< U), 5-aminoallyl-uridine, 5-halo-uridine (e.g., 5-iodo-uridine or 5-bromo-uridine), uridine 5-oxyacetic acid (cmo 5< U), uridine 5-oxyacetic acid methyl ester (mcmo 5< U), 5-carboxymethyl-uridine (cm 5< U), 1-carboxymethyl-pseudouridine, 5-carboxyhydroxymethyl-uridine (chm 5< U), 5-carboxyhydroxymethyl-uridine methyl ester (mchm 5< U), 5-methoxycarbonylmethyl-uridine (mcm 5< U), 5-methoxycarbonylmethyl-2-thio-uridine (mcm 5< s 2< U), 5-aminomethyl-2-thio-uridine (nm 5< s 2< U), 5-methylaminomethyl-uridine (mnm 5< U), 1-ethyl-pseudouridine, 5-methylaminomethyl-2-thio-uridine (mnm 5< s 2< U), 5-methylaminomethyl-2-seleno-uridine (mnm 5< se 2< U), 5-carbamoylmethyl-uridine (ncm 5< U), 5-carboxymethylaminomethyl-uridine (cmnm 5< U), 5-carboxymethylaminomethyl-2-thio-uridine (cmnm 5< s 2< U), 5-propynyl-uridine, 1-propynyl-pseudouridine, 5-taurinomethyl-uridine (τm 5< U), 1-taurinomethyl-pseudouridine, 5-taurinomethyl-2-thio-uridine(τm5s2U), 1-taurinomethyl-4-thio-pseudouridine), 5-methyl-2-thio-uridine (m 5< s 2< U), 1-methyl-4-thio-pseudouridine (m 1< s 4< ψ), 4-thio-1-methyl-pseudouridine, 3-methyl-pseudouridine (m 3< ψ), 2-thio-1-methyl-pseudouridine, 1-methyl-1-deaza-pseudouridine, 2-thio-1-methyl-1-deaza-pseudouridine, dihydrouridine (D), dihydropseudouridine, 5,6-dihydrouridine, 5-methyl-dihydrouridine (m 5< D), 2-thio-dihydrouridine, 2-thio-dihydropseudouridine, 2-methoxy-uridine, 2-methoxy-4-thio-uridine, 4-methoxy-pseudouridine, 4-methoxy-2-thio-pseudouridine, N1-methyl-pseudouridine, 3-(3-amino-3-carboxypropyl)uridine (acp 3< U), 1-methyl-3-(3-amino-3-carboxypropyl)pseudouridine (acp 3< ψ), 5-(isopentenylaminomethyl)uridine (inm 5< U), 5-(isopentenylaminomethyl)-2-thio-uridine (inm 5< s 2< U), α-thio-uridine, 2'-O-methyl-uridine (Um), 5,2'-O-dimethyl-uridine (m 5< Um), 2'-O-methyl-pseudouridine (ψm), 2-thio-2'-O-methyl-uridine (s 2< Um), 5-methoxycarbonylmethyl-2'-O-methyl-uridine (mcm 5< Um), 5-carbamoylmethyl-2'-O-methyl-uridine (ncm 5< Um), 5-carboxymethylaminomethyl-2'-O-methyl-uridine (cmnm 5< Um), 3,2'-O-dimethyl-uridine (m 3< Um), 5-(isopentenylaminomethyl)-2'-O-methyl-uridine (inm 5< Um), 1-thio-uridine, deoxythymidine, 2'-F-ara-uridine, 2'-F-uridine, 2'-OH-ara-uridine, 5-(2-carbomethoxyvinyl) uridine, and 5-[3-(1-E-propenylamino)uridine. In certain embodiments, the nucleoside comprising a modified nucleobase is pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ) or 5-methyl-uridine (m5U), in particular N1-methyl-pseudouridine.

[0420] In some embodiments, the replacement of one or more uridines with a nucleoside comprising a modified nucleobase comprises a replacement of at least 1%, at least 2%, at least 3%, at least 4%, at least 5%, at least 10%, at least 25%, at least 50%, at least 75%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% of the uridines. During synthesis of mRNA by in vitro transcription (IVT) using T7 RNA polymerase significant amounts of aberrant products, including double-stranded RNA (dsRNA) are produced due to unconventional activity of the enzyme. dsRNA induces inflammatory cytokines and activates effector enzymes leading to protein synthesis inhibition. Formation of dsRNA can be limited during synthesis of mRNA by in vitro transcription (IVT), for example, by limiting the amount of uridine triphosphate (UTP) during synthesis. Optionally, UTP may be added once or several times during synthesis of mRNA. Also, dsRNA can be removed from RNA such as IVT RNA, for example, by ion-pair reversed phase HPLC using a non-porous or porous C-18 polystyrene-divinylbenzene (PS-DVB) matrix. Alternatively, an enzymatic based method using E. coli RNaselll that specifically hydrolyzes dsRNA but not ssRNA, thereby eliminating dsRNA contaminants from IVT RNA preparations can be used. Furthermore, dsRNA can be separated from ssRNA by using a cellulose material. In some embodiments, an RNA preparation is contacted with a cellulose material and the ssRNA is separated from the cellulose material under conditions which allow binding of dsRNA to the cellulose material and do not allow binding of ssRNA to the cellulose material. Suitable methods for providing ssRNA are disclosed, for example, in WO 2017 / 182524.

[0421] As the term is used herein, "remove" or "removal" refers to the characteristic of a population of first substances, such as non-immunogenic RNA, being separated from the proximity of a population of second substances, such as dsRNA, wherein the population of first substances is not necessarily devoid of the second substance, and the population of second substances is not necessarily devoid of the first substance. However, a population of first substances characterized by the removal of a population of second substances has a measurably lower content of second substances as compared to the non-separated mixture of first and second substances.

[0422] In some embodiments, the amount of double-stranded RNA (dsRNA) is limited, e.g., dsRNA (especially dsmRNA) is removed from non-immunogenic RNA , such that less than 10%, less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, less than 0.3%, less than 0.1%, less than 0.05%, less than 0.03%, less than 0.01%, less than 0.005%, less than 0.004%, less than 0.003%, less than 0.002%, less than 0.001%, or less than 0.0005% of the RNA in the non-immunogenic RNA composition is dsRNA. In some embodiments, the non-immunogenic RNA (especially mRNA) is free or essentially free of dsRNA. In some embodiments, the non-immunogenic RNA (especially mRNA) composition comprises a purified preparation of single-stranded nucleoside modified RNA. In some embodiments, the non-immunogenic RNA (especially mRNA) composition comprises single-stranded nucleoside modified RNA (especially mRNA) and is substantially free of double stranded RNA (dsRNA). In some embodiments, the non-immunogenic RNA (especially mRNA) composition comprises at least 90%, at least 91%, at least 92%, at least 93 %, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, at least 99.5%, at least 99.9%, at least 99.99%, at least 99.991%, at least 99.992%, , at least 99.993%,, at least 99.994%, , at least 99.995%, at least 99.996%, at least 99.997%, or at least 99.998% single stranded nucleoside modified RNA, relative to all other nucleic acid molecules (DNA, dsRNA, etc.).

[0423] Various methods can be used to determine the amount of dsRNA. For example, a sample may be contacted with dsRNA-specific antibody and the amount of antibody binding to RNA may be taken as a measure for the amount of dsRNA in the sample. A sample containing a known amount of dsRNA may be used as a reference.

[0424] For example, RNA may be spotted onto a membrane, e.g., nylon blotting membrane. The membrane may be blocked, e.g., in TBS-T buffer (20 mM TRIS pH 7.4, 137 mM NaCl, 0.1% (v / v) TWEEN-20) containing 5% (w / v) skim milk powder. For detection of dsRNA, the membrane may be incubated with dsRNA-specific antibody, e.g., dsRNA-specific mouse mAb (English & Scientific Consulting, Szirák, Hungary). After washing, e.g., with TBS-T, the membrane may be incubated with a secondary antibody, e.g., HRP-conjugated donkey anti-mouse IgG (Jackson ImmunoResearch, Cat #715-035-150), and the signal provided by the secondary antibody may be detected.

[0425] In some embodiments, the non-immunogenic RNA (especially mRNA) is translated in a cell more efficiently than standard RNA with the same sequence. In some embodiments, translation is enhanced by a factor of 2-fold relative to its unmodified counterpart. In some embodiments, translation is enhanced by a 3-fold factor. In some embodiments, translation is enhanced by a 4-fold factor. In some embodiments, translation is enhanced by a 5-fold factor. In some embodiments, translation is enhanced by a 6-fold factor. In some embodiments, translation is enhanced by a 7-fold factor. In some embodiments, translation is enhanced by an 8-fold factor. In some embodiments, translation is enhanced by a 9-fold factor. In some embodiments, translation is enhanced by a 10-fold factor. In some embodiments, translation is enhanced by a 15-fold factor. In some embodiments, translation is enhanced by a 20-fold factor. In some embodiments, translation is enhanced by a 50-fold factor. In some embodiments, translation is enhanced by a 100-fold factor. In some embodiments, translation is enhanced by a 200-fold factor. In some embodiments, translation is enhanced by a 500-fold factor. In some embodiments, translation is enhanced by a 1000-fold factor. In some embodiments, translation is enhanced by a 2000-fold factor. In some embodiments, the factor is 10-1000-fold. In some embodiments, the factor is 10-100-fold. In some embodiments, the factor is 10-200-fold. In some embodiments, the factor is 10-300-fold. In some embodiments, the factor is 10-500-fold. In some embodiments, the factor is 20-1000-fold. In some embodiments, the factor is 30-1000-fold. In some embodiments, the factor is 50-1000-fold. In some embodiments, the factor is 100-1000-fold. In some embodiments, the factor is 200-1000-fold. In some embodiments, translation is enhanced by any other significant amount or range of amounts.

[0426] In some embodiments, the non-immunogenic RNA (especially mRNA) exhibits significantly less innate immunogenicity than standard RNA with the same sequence. In some embodiments, the non-immunogenic RNA (especially mRNA) exhibits an innate immune response that is 2-fold less than its unmodified counterpart. In some embodiments, innate immunogenicity is reduced by a 3-fold factor. In some embodiments, innate immunogenicity is reduced by a 4-fold factor. In some embodiments, innate immunogenicity is reduced by a 5-fold factor. In some embodiments, innate immunogenicity is reduced by a 6-fold factor. In some embodiments, innate immunogenicity is reduced by a 7-fold factor. In some embodiments, innate immunogenicity is reduced by an 8-fold factor. In some embodiments, innate immunogenicity is reduced by a 9-fold factor. In some embodiments, innate immunogenicity is reduced by a 10-fold factor. In some embodiments, innate immunogenicity is reduced by a 15-fold factor. In some embodiments, innate immunogenicity is reduced by a 20-fold factor. In some embodiments, innate immunogenicity is reduced by a 50-fold factor. In some embodiments, innate immunogenicity is reduced by a 100-fold factor. In some embodiments, innate immunogenicity is reduced by a 200-fold factor. In some embodiments, innate immunogenicity is reduced by a 500-fold factor. In some embodiments, innate immunogenicity is reduced by a 1000-fold factor. In some embodiments, innate immunogenicity is reduced by a 2000-fold factor.

[0427] The term "exhibits significantly less innate immunogenicity" refers to a detectable decrease in innate immunogenicity. In some embodiments, the term refers to a decrease such that an effective amount of the non-immunogenic RNA (especially mRNA) can be administered without triggering a detectable innate immune response. In some embodiments, the term refers to a decrease such that the non-immunogenic RNA (especially mRNA) can be repeatedly administered without eliciting an innate immune response sufficient to detectably reduce production of the protein encoded by the non-immunogenic RNA. In some embodiments, the decrease is such that the non-immunogenic RNA (especially mRNA) can be repeatedly administered without eliciting an innate immune response sufficient to eliminate detectable production of the protein encoded by the non-immunogenic RNA.

[0428] "Immunogenicity" is the ability of a foreign substance, such as RNA, to provoke an immune response in the body of a human or other animal. The innate immune system is the component of the immune system that is relatively unspecific and immediate. It is one of two main components of the vertebrate immune system, along with the adaptive immune system.Particles

[0429] Nucleic acids such as RNA, in particular mRNA, described herein may be present in particles comprising (i) the nucleic acid, and (ii) at least one cationic or cationically ionizable compound such as a polymer or lipid complexing the nucleic acid. Electrostatic interactions between positively charged molecules such as polymers and lipids and negatively charged nucleic acid are involved in particle formation. This results in complexation and spontaneous formation of nucleic acid particles. During the manufacturing process, introduction of an aqueous solution of RNA to an ethanolic lipid mixture containing a cationically ionizable lipid at pH of, e.g., 5 leads to an electrostatic interaction between the negatively charged RNA drug substance and the positively charged cationically ionizable lipid. This electrostatic interaction leads to particle formation coincident with efficient encapsulation of RNA drug substance. After RNA encapsulation, adjustment of the medium surrounding the resulting RNA-LNP to, e.g., pH 8 results in neutralization of the surface charge on the LNP. When all other variables are held constant, charge-neutral particles display longer in vivo circulation lifetimes and better delivery to hepatocytes compared to charged particles, which are cleared rapidly by the reticuloendothelial system. Upon endosomal uptake, the low pH of the endosome renders the LNP fusogenic and allows for release of the RNA into the cytosol of the target cell.

[0430] Different types of RNA containing particles have been described previously to be suitable for delivery of RNA in particulate form (cf., e.g., Kaczmarek, J. C. et al., 2017, Genome Medicine 9, 60). For non-viral RNA delivery vehicles, nanoparticle encapsulation of RNA physically protects RNA from degradation and, depending on the specific chemistry, can aid in cellular uptake and endosomal escape.

[0431] In the context of the present disclosure, the term "particle" relates to a structured entity formed by molecules or molecule complexes, in particular particle forming compounds. In some embodiments, the particle contains an envelope (e.g., one or more layers or lamellas) made of one or more types of amphiphilic substances (e.g., amphiphilic lipids). In this context, the expression "amphiphilic substance" means that the substance possesses both hydrophilic and lipophilic properties. The envelope may also comprise additional substances (e.g., additional lipids) which do not have to be amphiphilic. Thus, the particle may be a monolamellar or multilamellar structure, wherein the substances constituting the one or more layers or lamellas comprise one or more types of amphiphilic substances (in particular selected from the group consisting of amphiphilic lipids) optionally in combination with additional substances (e.g., additional lipids) which do not have to be amphiphilic. In some embodiments, the term "particle" relates to a micro- or nano-sized structure, such as a micro-or nano-sized compact structure. According to the present disclosure, the term "particle" includes nanoparticles.

[0432] An "RNA particle" can be used to deliver RNA to a target site of interest (e.g., cell, tissue, organ, and the like). An RNA particle may be formed from lipids comprising at least one cationic or cationically ionizable lipid. Without intending to be bound by any theory, it is believed that the cationic or cationically ionizable lipid combines together with the RNA to form aggregates, and this aggregation results in colloidally stable particles.

[0433] RNA particles described herein include lipid nanoparticle (LNP)-based and lipoplex (LPX)-based formulations.

[0434] A lipoplex (LPX) described herein is obtainable from mixing two aqueous phases, namely a phase comprising RNA and a phase comprising a dispersion of lipids. In some embodiments, the lipid phase comprises liposomes.

[0435] In some embodiments, liposomes are self-closed unilamellar or multilamellar vesicular particles wherein the lamellae comprise lipid bilayers and the encapsulated lumen comprises an aqueous phase. A prerequisite for using liposomes for nanoparticle formation is that the lipids in the mixture as required are able to form lamellar (bilayer) phases in the applied aqueous environment.

[0436] In some embodiments, liposomes comprise unilamellar or multilamellar phospholipid bilayers enclosing an aqueous core (also referred to herein as an aqueous lumen). They may be prepared from materials possessing polar head (hydrophilic) groups and nonpolar tail (hydrophobic) groups. In some embodiments, cationic lipids employed in formulating liposomes designed for the delivery of nucleic acids are amphiphilic in nature and consist of a positively charged (cationic) amine head group linked to a hydrocarbon chain or cholesterol derivative via glycerol.

[0437] In some embodiments, lipoplexes are multilamellar liposome-based formulations that form upon electrostatic interaction of cationic liposomes with RNAs. In some embodiments, formed lipoplexes possess distinct internal arrangements of molecules that arise due to the transformation from liposomal structure into compact RNA-lipoplexes.

[0438] In some embodiments, an LPX particle comprises an amphiphilic lipid, in particular cationic or cationically ionizable amphiphilic lipid, and RNA (especially mRNA) as described herein. In some embodiments, electrostatic interactions between positively charged liposomes (made from one or more amphiphilic lipids, in particular cationic or cationically ionizable amphiphilic lipids) and negatively charged RNA (especially mRNA) results in complexation and spontaneous formation of RNA lipoplex particles. Positively charged liposomes may be generally synthesized using a cationic or cationically ionizable amphiphilic lipid, such as a cationically ionizable lipid of formula (I), DOTMA and / or DODMA, and optionally additional lipids, such as DOPE or DSPC. In some embodiments, an RNA (especially mRNA) lipoplex particle is a nanoparticle.

[0439] In general, a lipid nanoparticle (LNP) is obtainable from direct mixing of RNA in an aqueous phase with lipids in a phase comprising an organic solvent, such as ethanol. In that case, lipids or lipid mixtures can be used for particle formation, which do not form lamellar (bilayer) phases in water.

[0440] In some embodiments, LNPs comprise or consist of a cationic / cationically ionizable lipid (in particular, a cationically ionizable lipid of any one of the formulas (I), (Ia), (Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (li), (Ij), (IIa), (IIb), (IIIa), (IIIb), (IV-1), (IV-2), and (IV-3) disclosed herein) and helper lipids such as phospholipids, cholesterol, and / or polymer-conjugated lipids (e.g., polyethylene glycol (PEG) lipids or sarcosinylated lipids). In some embodiments, in the RNA LNPs described herein the RNA (in particular, mRNA) is bound by cationically ionizable lipid (in particular a cationically ionizable lipid of any one of the formulas (I), (Ia), (Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (IIa), (IIb), (IIIa), (IIIb), (IV-1), (IV-2), and (IV-3) disclosed herein) that occupies the central core of the LNP. In some embodiments, polymer-conjugated lipid forms the surface of the LNP, along with phospholipids. In some embodiments, the surface comprises a bilayer. In some embodiments, cholesterol and cationically ionizable lipid (in particular a cationically ionizable lipid of any one of the formulas (I), (Ia), (Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (IIa), (IIb), (Illa), (IIIb), (IV-1), (IV-2), and (IV-3) disclosed herein) in charged and uncharged forms can be distributed throughout the LNP.

[0441] In some embodiments, RNA (e.g., mRNA) described herein may be noncovalently associated with a particle as described herein. In embodiments, the RNA (especially mRNA) may be adhered to the outer surface of the particle (surface RNA (especially surface mRNA)) and / or may be contained in the particle (encapsulated RNA (especially encapsulated mRNA)).

[0442] In some embodiments, the particles (e.g., LNPs and LPXs) described herein have a size (such as a diameter) in the range of about 10 to about 2000 nm, such as at least about 15 nm (e.g., at least about 20 nm, at least about 25 nm, at least about 30 nm, at least about 35 nm, at least about 40 nm, at least about 45 nm, at least about 50 nm, at least about 55 nm, at least about 60 nm, at least about 65 nm, at least about 70 nm, at least about 75 nm, at least about 80 nm, at least about 85 nm, at least about 90 nm, at least about 95 nm, or at least about 100 nm) and / or at most about 1900 nm (e.g., at most about 1800 nm, at most about 1700 nm, at most about 1600 nm, at most about 1500 nm, at most about 1400 nm, at most about 1300 nm, at most about 1200 nm, at most about 1100 nm, at most about 1000 nm, at most about 950 nm, at most about 900 nm, at most about 850 nm, at most about 800 nm, at most about 750 nm, at most about 700 nm, at most about 650 nm, at most about 600 nm, at most about 550 nm, or at most about 500 nm), such as in the range of about 20 to about 1500 nm, such as about 30 to about 1200 nm, about 40 to about 1100 nm, about 50 to about 1000 nm, about 60 to about 900 nm, about 70 to about 800 nm, about 80 to about 700 nm, about 90 to about 600 nm, or about 50 to about 500 nm or about 100 to about 500 nm, such as in the range of 10 to 1000 nm, 15 to 500 nm, 20 to 450 nm, 25 to 400 nm, 30 to 350 nm, 40 to 300 nm, 50 to 250 nm, 60 to 200 nm, 70 to 150 nm, or 80 to 150 nm. In some embodiments, the particles (e.g., LNPs and LPXs) described herein have a size (such as a diameter) in the range of from about 40 nm to about 200 nm, such as from about 50 nm to about 180 nm, from about 60 nm to about 160 nm, from about 80 nm to about 150 nm or from about 80 nm to about 120 nm.

[0443] In some embodiments, the particles (e.g., LNPs and LPXs) described herein have an average diameter that in some embodiments ranges from about 50 nm to about 1000 nm, from about 50 nm to about 800 nm, from about 50 nm to about 700 nm, from about 50 nm to about 600 nm, from about 50 nm to about 500 nm, from about 50 nm to about 450 nm, from about 50 nm to about 400 nm, from about 50 nm to about 350 nm, from about 50 nm to about 300 nm, from about 50 nm to about 250 nm, from about 50 nm to about 200 nm, from about 100 nm to about 1000 nm, from about 100 nm to about 800 nm, from about 100 nm to about 700 nm, from about 100 nm to about 600 nm, from about 100 nm to about 500 nm, from about 100 nm to about 450 nm, from about 100 nm to about 400 nm, from about 100 nm to about 350 nm, from about 100 nm to about 300 nm, from about 100 nm to about 250 nm, from about 100 nm to about 200 nm, from about 150 nm to about 1000 nm, from about 150 nm to about 800 nm, from about 150 nm to about 700 nm, from about 150 nm to about 600 nm, from about 150 nm to about 500 nm, from about 150 nm to about 450 nm, from about 150 nm to about 400 nm, from about 150 nm to about 350 nm, from about 150 nm to about 300 nm, from about 150 nm to about 250 nm, from about 150 nm to about 200 nm, from about 200 nm to about 1000 nm, from about 200 nm to about 800 nm, from about 200 nm to about 700 nm, from about 200 nm to about 600 nm, from about 200 nm to about 500 nm, from about 200 nm to about 450 nm, from about 200 nm to about 400 nm, from about 200 nm to about 350 nm, from about 200 nm to about 300 nm, from about 200 nm to about 250 nm, or from about 80 to about 150 nm. In some embodiments, the particles (e.g., LNPs and LPXs) described herein have an average diameter that in some embodiments ranges from about 40 nm to about 200 nm, such as from about 50 nm to about 180 nm, from about 60 nm to about 160 nm, from about 80 nm to about 150 nm or from about 80 nm to about 120 nm.

[0444] In some embodiments, the particles described herein are nanoparticles. The term "nanoparticle" relates to a nano-sized particle comprising nucleic acid (especially mRNA) as described herein and at least one cationic or cationically ionizable lipid, wherein all three external dimensions of the particle are in the nanoscale, i.e., at least about 1 nm and below about 1000 nm. Preferably, the size of a particle is its diameter.

[0445] RNA particles (especially mRNA particles) described herein may exhibit a polydispersity index (PDI) less than about 0.5, less than about 0.4, less than about 0.3, less than about 0.2, less than about 0.1, or less than about 0.05. By way of example, the nucleic acid particles can exhibit a polydispersity index in a range of about 0.01 to about 0.4 or about 0.1 to about 0.3. The N / P ratio gives the ratio of the nitrogen groups in the lipid to the number of phosphate groups in the nucleic acid. It is correlated to the charge ratio, as the nitrogen atoms (depending on the pH) are usually positively charged and the phosphate groups are negatively charged. The N / P ratio, where a charge equilibrium exists, depends on the pH. Lipid formulations are frequently formed at N / P ratios larger than four up to twelve, because positively charged nanoparticles are considered favorable for transfection. In that case, RNA is considered to be completely bound to nanoparticles.

[0446] RNA particles (especially mRNA particles) described herein can be prepared using a wide range of methods that may involve obtaining a colloid from at least one cationic or cationically ionizable lipid and mixing the colloid with nucleic acid to obtain nucleic acid particles.

[0447] The term "colloid" as used herein relates to a type of homogeneous mixture in which dispersed particles do not settle out. The insoluble particles in the mixture are microscopic, with particle sizes between 1 and 1000 nanometers. The mixture may be termed a colloid or a colloidal suspension. Sometimes the term "colloid" only refers to the particles in the mixture and not the entire suspension.

[0448] For the preparation of colloids comprising at least one cationic or cationically ionizable lipid methods are applicable herein that are conventionally used for preparing liposomal vesicles and are appropriately adapted. The most commonly used methods for preparing liposomal vesicles share the following fundamental stages: (i) lipids dissolution in organic solvents, (ii) drying of the resultant solution, and (iii) hydration of dried lipid (using various aqueous media). In the film hydration method, lipids are firstly dissolved in a suitable organic solvent, and dried down to yield a thin film at the bottom of the flask. The obtained lipid film is hydrated using an appropriate aqueous medium to produce a liposomal dispersion. Furthermore, an additional downsizing step may be included.

[0449] Reverse phase evaporation is an alternative method to the film hydration for preparing liposomal vesicles that involves formation of a water-in-oil emulsion between an aqueous phase and an organic phase containing lipids. A brief sonication of this mixture is required for system homogenization. The removal of the organic ...

Claims

1. A composition comprising: (i) RNA; (ii) a cationically ionizable lipid comprising the structure of the following formula (I): wherein each of R1 and R2 is independently R5 or -G1-L1-R6, wherein at least one of R1 and R2 is -G1-L1-R6; each of R3 and R4 is independently selected from the group consisting of C1-6 alkyl, C2-6 alkenyl, aryl, and C3-10 cycloalkyl; each of R5 and R6 is independently a non-cyclic hydrocarbyl group having at least 10 carbon atoms; each of G1 and G2 is independently unsubstituted C1-12 alkylene or C2-12 alkenylene; each of L1 and L2 is independently selected from the group consisting of -O(C=O)-, -(C=O)O-, -C(=O)-, -O-, -S(O)x-, -S-S-, -C(=O)S-, -SC(=O)-, -NRaC(=O)-, -C(=O)NRa-, -NRaC(=O)NRa-, -OC(=O)NRa- and -NRaC(=O)O-; Ra is H or C1-12 alkyl; m is 0, 1, 2, 3, or 4; and x is 0, 1 or 2; and (iii) at least one polysarcosine-conjugated lipid.

2. The composition of claim 1, wherein (i) each L1 is independently selected from the group consisting of -O(C=O)-, -(C=O)O-, -C(=O)S-, -SC(=O)-, -NRaC(=O)-, and -C(=O)NRa-, preferably each L1 is independently -O(C=O)- or -(C=O)O-; (ii) L2 is selected from the group consisting of -O(C=O)-, -(C=O)O-, -C(=O)-, -C(=O)S-, -SC(=O)-, -NRaC(=O)-, and -C(=O)NRa-, preferably L2 is -O(C=O)- or -(C=O)O-; (iii) R5 is a straight alkyl or alkenyl group having at least 10 carbon atoms, preferably at least 14 carbon atoms, more preferably at least 16 carbon atoms; (iv) R5 is a straight alkyl group or a straight alkenyl group having at least 2 carbon-carbon double bonds; (v) R5 has the following structure: wherein represents the bond by which R5 is bound to the remainder of the compound; (vi) each G1 is independently unsubstituted straight C1-12 alkylene or C2-12 alkenylene, preferably unsubstituted, straight C6-12 alkylene or C6-12 alkenylene, more preferably unsubstituted, straight C8-12 alkylene or C8-12 alkenylene, or unsubstituted straight C6-10 alkylene or C6-10 alkenylene, such as unsubstituted straight C8 alkylene; (vii) each R6 is independently a straight hydrocarbyl group having at least 10 carbon atoms; (viii) each R6 is attached to L1 via an internal carbon atom of R6; (ix) each R6 is independently selected from the group consisting of: and wherein represents the bond by which R6 is bound to L1; (x) one of R1 and R2 is R5 and the other is -G1-L1-R6, or each of R1 and R2 is independently -G1-L1-R6; (xi) each of R3 and R4 is independently C1-6 alkyl or C2-6 alkenyl, preferably C1-4 alkyl or C2-4 alkenyl, more preferably C1-3 alkyl, such as methyl or ethyl; (xii) G2 is unsubstituted C2-10 alkylene or C2-10 alkenylene, preferably unsubstituted C2-6 alkylene or C2-6 alkenylene, more preferably unsubstituted C2-4 alkylene or C2-4 alkenylene, such as ethylene or trimethylene; and / or (xiii) m is 0, 1, 2 or 3, preferably 0 or 2.

3. The composition of claim 1 or 2, wherein (i) the cationically ionizable lipid comprises the structure of one of the following formulas (IIIa) or (IIIb): wherein each of R3 and R4 is independently C1-4 alkyl or C2-4 alkenyl, more preferably C1-3 alkyl, such as methyl or ethyl; R5 is a straight alkyl or alkenyl group having at least 16 carbon atoms, wherein the alkenyl group preferably has at least 2 carbon-carbon double bonds; each R6 is independently a straight hydrocarbyl group having at least 10 carbon atoms, wherein R6 is attached to L1 via an internal carbon atom of R6; each G1 is independently unsubstituted, straight C6-12 alkylene or C6-12 alkenylene, e.g., unsubstituted, straight C8-10 alkylene or C8-10 alkenylene, such as unsubstituted, straight C8 alkylene; G2 is unsubstituted C2-6 alkylene or C2-6 alkenylene, preferably unsubstituted C2-4 alkylene or C2-4 alkenylene, such as ethylene or trimethylene; each of L1 and L2 is independently -O(C=O)- or -(C=O)O-; and m is 0, 1, 2 or 3, preferably 0 or 2; (ii) the cationically ionizable lipid comprises one of the following structures (IV-1), (IV-2), and (IV-3): and / or (iii) the cationically ionizable lipid comprises from 20 mol % to 80 mol %, preferably from 25 mol % to 65 mol %, more preferably from 30 mol % to 50 mol %, such as from 40 mol % to 50 mol %, or from 55 mol % to 65 mol % of the total lipid present in the composition.

4. The composition of any one of claims 1 to 3, wherein (i) the polysarcosine comprises between 2 and 200 sarcosine units, preferably between 5 and 100 sarcosine units, more preferably between 10 and 50 sarcosine units, more preferably between 15 and 40 sarcosine units, more preferably about 23 sarcosine units; (ii) the polysarcosine-conjugated lipid comprises the structure of the following general formula (V): wherein x is the number of sarcosine units; (iii) the polysarcosine-conjugated lipid has the structure of the following general formula (VI): wherein one of R1 and R2 comprises a hydrophobic group and the other is H, a hydrophilic group or a functional group optionally comprising a targeting moiety; and x is the number of sarcosine units, wherein, optionally, R1 is H, a hydrophilic group or a functional group optionally comprising a targeting moiety; and R2 comprises one or two straight alkyl or alkenyl groups each having at least 12 carbon atoms, preferably at least 14 carbon atoms; (iv) the polysarcosine-conjugated lipid has the structure of the following general formula (VII): wherein R is H, a hydrophilic group or a functional group optionally comprising a targeting moiety; and x is the number of sarcosine units; (v) the polysarcosine-conjugated lipid has the structure of the following formula: wherein n is 23; and / or (vi) the polysarcosine-conjugated lipid comprises from 0.1 mol % to 5 mol %, preferably from 0.5 mol % to 4.5 mol %, more preferably from 1 mol % to 4 mol %, such as 3 mol % to 4 mol %, of the total lipid present in the composition.

5. The composition of any one of claims 1 to 4, wherein the composition further comprises one or more additional lipids, preferably selected from the group consisting of phospholipids, steroids, and combinations thereof, more preferably the composition comprises the cationically ionizable lipid; a polymer-conjugated lipid, preferably selected from a polysarcosine-conjugated lipid and a pegylated lipid; a phospholipid; and a steroid.

6. The composition of claim 5, wherein (i) the phospholipid is selected from the group consisting of phosphatidylcholines, phosphatidylethanolamines, phosphatidylglycerols, phosphatidic acids, phosphatidylserines and sphingomyelins, more preferably selected from the group consisting of distearoylphosphatidylcholine (DSPC), dioleoylphosphatidylcholine (DOPC), dimyristoylphosphatidylcholine (DMPC), dipentadecanoylphosphatidylcholine, dilauroylphosphatidylcholine, dipalmitoylphosphatidylcholine (DPPC), diarachidoylphosphatidylcholine (DAPC), dibehenoylphosphatidylcholine (DBPC), ditricosanoylphosphatidylcholine (DTPC), dilignoceroylphatidylcholine (DLPC), palmitoyloleoyl-phosphatidylcholine (POPC), 1,2-di-O-octadecenyl-sn-glycero-3-phosphocholine (18:0 Diether PC), 1-oleoyl-2-cholesterylhemisuccinoyl-sn-glycero-3-phosphocholine (OChemsPC), 1-hexadecyl-sn-glycero-3-phosphocholine (C16 Lyso PC), dioleoylphosphatidylethanolamine (DOPE), distearoyl-phosphatidylethanolamine (DSPE), dipalmitoyl-phosphatidylethanolamine (DPPE), dimyristoyl-phosphatidylethanolamine (DMPE), dilauroyl-phosphatidylethanolamine (DLPE), and diphytanoyl-phosphatidylethanolamine (DPyPE); (ii) the phospholipid comprises from 5 mol % to 40 mol %, preferably from 5 mol % to 20 mol %, more preferably from 5 mol % to 15 mol % of the total lipid present in the composition; (iii) the steroid comprises a sterol such as cholesterol; (iv) the steroid comprises from 10 mol % to 65 mol %, preferably from 20 mol % to 60 mol %, more preferably from 30 mol % to 50 mol % or from 25 mol % to 35 mol % of the total lipid present in the composition; and / or (v) wherein the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from 30 mol % to 50 mol %, such as from 40 mol % to 50 mol %, of the total lipid present in the composition; the polysarcosine-conjugated lipid comprises from 1 mol % to 4.5 mol % of the total lipid present in the composition; the phospholipid comprises from 5 mol % to 15 mol % of the total lipid present in the composition; and the steroid comprises from 30 mol % to 50 mol % of the total lipid present in the composition; or the composition comprises the cationically ionizable lipid, a polysarcosine-conjugated lipid, a phospholipid, and a steroid, wherein the cationically ionizable lipid comprises from 55 mol % to 65 mol % of the total lipid present in the composition; the polysarcosine-conjugated lipid comprises from 1 mol % to 4.5 mol % of the total lipid present in the composition; the phospholipid comprises from 5 mol % to 15 mol % of the total lipid present in the composition; and the steroid comprises from 25 mol % to 35 mol % of the total lipid present in the composition.

7. The composition of any one of claims 1 to 6, wherein (i) at least a portion of (i) the RNA, (ii) the cationically ionizable lipid, and, if present, (iii) the one or more additional lipids is present in nanoparticles, such as lipid nanoparticles (LNPs), wherein, optionally, the nanoparticles have a size of from 30 nm to 500 nm; (ii) the RNA is mRNA; (iii) the RNA (a) comprises a modified nucleoside in place of uridine, wherein the modified nucleoside is preferably selected from pseudouridine (ψ), N1-methyl-pseudouridine (m1ψ), and 5-methyl-uridine (m5U); (b) has a coding sequence which is codon-optimized; and / or (c) has a coding sequence whose G / C content is increased compared to the wild-type coding sequence; and / or (iv) the RNA comprises at least one of the following, preferably all of the following: a 5' cap; a 5' UTR; a 3' UTR; and a poly-A sequence, wherein, optionally, (a) the poly-A sequence comprises at least 100 A nucleotides, wherein the poly-A sequence preferably is an interrupted sequence of A nucleotides; and / or (b) the 5' cap is a cap1 or cap2 structure.

8. The composition of any one of claims 1 to 7, wherein the RNA encodes one or more peptides or proteins, wherein preferably the one or more peptides or proteins are pharmaceutically active peptides or proteins and / or comprise an epitope for inducing an immune response against an antigen in a subject, wherein, optionally, (i) the pharmaceutically active peptide or protein and / or the antigen or epitope is derived from or is a SARS-CoV-2 spike (S) protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof; and / or (ii) the RNA comprises an open reading frame (ORF) encoding an amino acid sequence comprising a SARS-CoV-2 S protein, an immunogenic variant thereof, or an immunogenic fragment of the SARS-CoV-2 S protein or the immunogenic variant thereof, wherein, optionally, (a) the SARS-CoV-2 S protein variant has proline residue substitutions at positions 986 and 987 of SEQ ID NO: 11; (b) the SARS-CoV-2 S protein variant has at least 80% identity to the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 11 or the amino acid sequence of amino acids 17 to 1273 of SEQ ID NO: 12; (c) the fragment comprises the receptor binding domain (RBD) of the SARS-CoV-2 S protein; or (d) the fragment of (i) the SARS-CoV-2 S protein or (ii) the immunogenic variant of the SARS-CoV-2 S protein has at least 80% identity to the amino acid sequence of amino acids 327 to 528 of SEQ ID NO: 11.

9. The composition of any one of claims 1 to 8 for use in therapy.

10. The composition of any one of claims 1 to 8 for use in a method for delivering RNA to cells of a subject, the method comprising administering the composition to a subject.

11. The composition of any one of claims 1 to 8 for use in a method for delivering a pharmaceutically active peptide or protein to a subject, the method comprising administering the composition to a subject, wherein the RNA encodes the pharmaceutically active peptide or protein.

12. The composition of any one of claims 1 to 8 for use in a method for treating or preventing a disease or disorder in a subject, the method comprising administering the composition to a subject, wherein delivering the RNA to cells of the subject is beneficial in treating or preventing the disease or disorder.

13. The composition of any one of claims 1 to 8 for use in a method for treating or preventing a disease or disorder in a subject, the method comprising administering the composition to a subject, wherein the RNA encodes a pharmaceutically active peptide or protein and wherein delivering the pharmaceutically active peptide or protein to the subject is beneficial in treating or preventing the disease or disorder.

14. The composition of any one of claims 1 to 8 for use in inducing an immune response in a subject.

15. The composition for use of any one of claims 10 to 13, wherein the subject is a mammal, and wherein, optionally, the mammal is a human.